This .gitignore is not correct. At least was not working for me.
Ignoring /media/* and then excluding !/media/customer/.htaccess is not
working. According to the Git manual, "It is not possible to re-include
a file if a parent directory of that file is excluded."
(https://git-scm.com/docs/gitignore).

Found a solution here:
http://stackoverflow.com/questions/987142/make-gitignore-ignore-everything-except-a-few-files/16318111#16318111

Remove Composer's file and directory from Symfony.

Added BizTalk build output files to ignore list

TeX: remove duplicates

Added Telerik's JustMock configruation files

Added /project/project to PlayFramework.gitignore

https://www.playframework.com/documentation/2.5.x/Anatomy

[Python Gitignore] Ignore Sage's parsed files

Ignore Sage's parsed files (*.sage.py) that are left after running a .Sage program.

Ignore dictionaries to reflect docs

[Eclipse] Add excludes kept in Scala.gitignore .

[Scala] remove external tools excludes.

[SBT] Add some excludes kept in Scala.gitignore .

Scala.gitignore currently has more entries for SBT than SBT.gitignore itself.
Copy missing entries here.

Scala.gitignore currently has more entries for Eclipse than Eclipse.gitignore
itself. Copy missing entries here.

Remove excludes for SBT, Eclipse and ENSIME. They'll be added to appropriate
Global/ gitignore files.

[Scala] exclude Scala IDE related .cache-main .

Update TeX.gitignore

minitoc also generates .stc, .slf, and .slt files

updated link to fastlane docs

[Maven] fix comment

Add comment for Java .class files

Fix spelling

Add missing space for the last comment

fix(Node): ignore yarn logs

This adds ignores for the `yarn-debug.log*` and `yarn-error.log*` files sometimes produced by the [Yarn package manager](https://yarnpkg.com).

Ignoring more generated file for Java project

Codeigniter 3 support

[Node/VisualStudio] ignore typings directory

Added .gitignore for PureScript

Ignore ensime files

Add an explanation to reduce PHP framework clutter

[Magento] basic files that must be ignored