* Add units concept for modulable functions of a repository

* remove unused comment codes & fix lints and tests

* remove unused comment codes

* use struct config instead of map

* fix lint

* rm wrong files

* fix tests

* Added rel="noopener" to target="_blank" hrefs

* Replaced gogs.io/docs with docs.gitea.io

- Refactor code to use sync.UniqueQueue
- Closes #3509

Enable/disable input based on user chosen options for wiki and issue tracker.

Executed go fmt

getEngine() not handles DB parameters (#2972) (#2974)

Uses .AllCols() for Update in updateMirror()

Spanish traslation removed

Fixed a wrong way to ommit the --prune option in process.ExecDir() for MirrorUpdate function

Re: issues gogits/gogs#2863 and gogits/gogs#3231

As a result of modifications to the contents of the conf folder, `make bindata`
was run, causing an update to bindata.go.

Meta
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This commit will be rebased onto the 'develop' branch.

Closes #2764

- add border-radius to filter list items
- use color as background of label for issue/pull view page

Collaborators have write access as default, and can be changed via repository
collaboration settings page to change between read, write and admin.

This commit improves templates readability, since all of them use consistent
indent with all template command blocks indented too.

1. Indents both HTML containers such as <div>, <p> and Go HTML template blocks
   such as {{if}} {{with}}

2. Cleans all trailing white-space

3. Adds trailing last line-break to each file

Merges repo/sidebar.tmpl with repo/header.tmpl and makes every repo page use
middleware.RepoRef() necessary to display information on this menu.

This is more inline with way GitHub looks like and feels much more natural and
in style with rest of the interface.

- update locales
- update README