- added new 'make webpack' target
- deprecated 'make js' and 'make css'
- extend webpack config to load the less files
- updated docs

I had to rename the source file of `arc-green.less` to avoid generating
a useless JS entrypoint via webpack-fix-style-only-entries which would
not work with different source/destination filenames. I hear that there
should be cleaner solutions possible once we upgrade to Webpack 5.

Co-authored-by: zeripath <art27@cantab.net>

This changes the CSS output of webpack to output to the public/css
directory instead of inling CSS in JS. This enables CSS minification and
autoprefixer based on browserslist which would otherwise not be
possible.

The result of this change is two new output files currently:

- public/css/swagger.css
- public/css/gitgraph.css

Co-authored-by: techknowlogick <matti@mdranta.net>

Currently, this needs to be its own chunk because fomantic depends
on jQuery being present. The next step is to move fomantic to webpack
too after which we can combine the index,fomantic and jquery files into
one.

jquery-migrate is still neccessary because our ancient version of Dropzone
seems to break without it. I imagine it can be removed after a Dropzone
upgrade.

* Use npm to manage fomantic

* Only build needed semantic components

* Fix make

* Don't import fonts from google sites since we have loaded

* [misc] devendor fomantic-ui and rebuild upon src or config changes only

Signed-off-by: Jakob Ackermann <das7pad@outlook.com>

* Change sort alphabetically of semantic components

* Fix trailing slash

* fix makefile

* Remove dependency to gulp from package.json

* Fix something

* Simplife the makefile

* add missed fomantic compnent

Co-authored-by: Jakob Ackermann <das7pad@outlook.com>

Created a second webpack output file for swagger-ui which is loaded on
the /api/swagger route. One notable difference is the absence of the
swagger favicon that was previously used which is now the gitea icon. I
see no easy way to restore that favicon, so I decided to not keep it.

Co-authored-by: Antoine GIRARD <sapk@users.noreply.github.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

This is the result of `make npm-update`. I also fixed a minor linting
issue which came up with the eslint 6.7 update.

- moved gitgraph.js to web_src and made it importable and es6-compatible
- created new webpack chunk for gitgraph
- enabled CSS loader in webpack
- enabled async/await syntax via regenerator-runtime
- added script to ensure webpack chunks are loaded correctly
- disable terser's comment extraction to prevent .LICENCE files

gitgraph.js has many issues:

1. it is incompatible with ES6 because of strict-mode violations
1. it does not export anything
1. it's css has weird styles like for `body`
1. it is not available on npm

I fixed points 1-3 in our version so it's now loadable in webpack. We should eventually consider alternatives.

* modernize js and use babel

- add babel toolchain to transform modern JS to ES5
- extend eslint config for modern rules
- fixes linting issues via `eslint --fix` and manual fixes

* run 'make css' to satisfy CI

* code style tweaks and set js indendation to 2 in .editorconfig

* regenerate js

* Move index.js to web_src and use webpack

* Fix initHeatMap

* update eslint and move webpack to devDependencies

* update index.js

* add eslint env node

Bumps [eslint-utils](https://github.com/mysticatea/eslint-utils) from 1.3.1 to 1.4.2.
- [Release notes](https://github.com/mysticatea/eslint-utils/releases)
- [Commits](https://github.com/mysticatea/eslint-utils/compare/v1.3.1...v1.4.2)

Signed-off-by: dependabot[bot] <support@github.com>

this is the result of `make npm-update js css`

Bumps [lodash](https://github.com/lodash/lodash) from 4.17.11 to 4.17.14.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](https://github.com/lodash/lodash/compare/4.17.11...4.17.14)

Signed-off-by: dependabot[bot] <support@github.com>

- ran `make npm-update`
- ran `make js`, fixed new lint issue
- ran `make css`, this added back some vendor prefixes
- added `engines` property to package.json to specify minimum required
  Node.js version
- added `private` property to package.json to prevent accidential
  publishing to npm

New CSS linter which is much more powerfull than the previous one.
Configuration is default but I had to remove a few rules that were
throwing too many or weird errors.

More importantly, the linter will exit with code 1 on errors so now our
build will fail if the CSS linter fails which should eliminate linter
errors being introduced without notice.

* add 'npm' and 'npm-update' make targets and lockfile

- `make npm` installs and updates node_modules, triggered automatically
   on `make css` and `make js` as it completes reasonably fast and
   ensures consistent modules.
- `make npm-update` updates all dependencies to their latest version,
   regenerates `node_modules` from scratch and updates
   `package-lock.json`. It uses npm modules `updates` written by yours
   truly to find the latest version of each dependency.

* add suggested make dependencies

* remove package-lock.json during npm-update

* regenerate package-lock.json

* remove and disable package-lock

Using exact versions in package.json has the same effect as lockfiles
without all the troubles the lockfiles bring (different versions of
package manager generating different lockfiles primarily).

Ensured we only use exact versions in package.json and stopped
generation of new lockfiles via .npmrc which is support by both the npm
and yarn package managers.

Fixes: https://github.com/go-gitea/gitea/issues/6967

* enable save-exact

* add make targets for js,css, add javascript linter

- add `make js`, deprecating `make javascripts`
- add `make css`, deprecating `make generate-stylesheets` and
  `make stylesheets-check`
- changed the unclean css check to only run on CI
- add JS linting via eslint with basic configuration and fixed
  discovered issues
- changed autoprefixer to use official `postcss-cli` avoiding the need
  to loop in the makefile
- moved browserslist to package.json so other future tools can use it
  too.
- update documentation for new make targets and added JS section

* fix indentation

* move functions used in html to 'exported' list

* Run lessc binary without having to install anything to node_modules

* use relative paths to node bin scripts, removing npx

* Revert "use relative paths to node bin scripts, removing npx"

This reverts commit 119b725525.

* fix lessc and postcss plugins

* check for node_modules and use actual bin names

* Add autoprefixer to css build

* also use autoprefixer on theme files

This makes it easier for user who want to theme but
don't have the ability to know how to customize templates
all that is required is a change in a config option

The reason why I chose the DEFAULT_THEME as variable,
as perhaps in the future we will allow users to chose their
theme whon logged in just like we do with languages