Clean up various use of escape/unescape functions for URL generation (#6334)

* Use PathUnescape instead of QueryUnescape when working with branch names

Currently branch names with a '+' fail in certain situations because
QueryUnescape replaces the + character with a blank space.

Using PathUnescape should be better since it is defined as:

// PathUnescape is identical to QueryUnescape except that it does not
// unescape '+' to ' ' (space).

Fixes #6333

* Change error to match new function name

* Add new util function PathEscapeSegments

This function simply runs PathEscape on each segment of a path without
touching the forward slash itself. We want to use this instead of
PathEscape/QueryEscape in most cases because a forward slash is a valid name for a
branch etc... and we don't want that escaped in a URL.

Putting this in new file url.go and also moving a couple similar
functions into that file as well.

* Use EscapePathSegments where appropriate

Replace various uses of EscapePath/EscapeQuery with new
EscapePathSegments. Also remove uncessary uses of various
escape/unescape functions when the text had already been escaped or was
not escaped.

* Reformat comment to make drone build happy

* Remove no longer used url library

* Requested code changes

1 files changed, 1 insertions, 1 deletions

diff --git a/models/repo.go b/models/repo.go
index 2822f7d718..cafde29363 100644
--- a/models/repo.go
+++ b/models/repo.go
@@ -838,7 +838,7 @@ type CloneLink struct {
 
 // ComposeHTTPSCloneURL returns HTTPS clone URL based on given owner and repository name.
 func ComposeHTTPSCloneURL(owner, repo string) string {
-	return fmt.Sprintf("%s%s/%s.git", setting.AppURL, url.QueryEscape(owner), url.QueryEscape(repo))
+	return fmt.Sprintf("%s%s/%s.git", setting.AppURL, url.PathEscape(owner), url.PathEscape(repo))
 }
 
 func (repo *Repository) cloneLink(e Engine, isWiki bool) *CloneLink {