Unix() already uses UTC as timezone

os.Rename does not create parent directory automatically when not exist

RepoLink -> Link, RepoRelLink -> RelLink, FullRepoLink -> FullLink

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.

Since . and .. has browser automatical behaviors, we need to disallow those names.

Add start count corrector for Repository.NumClosedIssues

Fix #2872

Both are possible on explore and admin panel

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

- Migrate: #2704 #2653
- Clone: #2701
- Mirror, Pull

Improve test cases, config settings, also show SSH config settings on admin config panel.

Remote repository path is renamed but does not delete
outdated local copy which still has old repository path
as remote.

- Update locales