Indexed search of repository contents (for default branch only)

* Trigger sync webhooks on UI commit

* Also fix UI upload/delete

* Update code.gitea.io/git

* Update function calls

* govendor fetch

This change corrects a few logging issues:

 * Standardized formatting errors with '%v'.
 * Standardized failure warning word usage.
 * Corrected an instance of using the standard log library when
   the gitea log library should be used instead.

* Add a process.Manager singleton with process.GetManager()

* Use process.GetManager everywhere

* Fix godoc comments for process module

* Increment process counter id after locking the mutex

- Update import paths from github.com/go-gitea to code.gitea.io
- Fix import path for travis

See https://docs.travis-ci.com/user/languages/go#Go-Import-Path

* Replace gogits/git-module dependency with go-gitea/git

Fixes #92

* Remove git alias for git module import (not needed)