autocomplete issues and preload autocomplete data.

update jquery-atwho-rails to v0.3.0

add autocomplete_source action to project for gfm autocomplete

move init_autocomplete layout from head_panel to project_resource
Fix not using git.bin_path in config.

Closing #3614" and "Closing #3574.
Bump charlock_holmes to 0.9.6.4

Signed-off-by: Axilleas Pipinellis <axilleas@archlinux.gr>
Setting the working directory before git operations
Merge pull request #3874 from axilleas/installation-fix

Bump charlock_holmes to 0.9.6.4
Fixes #3793: Puma configuration for relative base URL
Merge pull request #3877 from mikehaertl/3793-puma-relative-url

Puma configuration for relative base URL
Merge pull request #3862 from crazyscience/patch-3

Setting the working directory before git operations
replace selectboxes with filters
init filter links
Add Gitlab::VersionInfo class to fix and simplify version check.

It returns "yes" if required version is "1.7.10" and current version is "1.6.10",
because the patch version of current version equals to that of required version.
bring more usability to issues filtering. Block issues area on loading filtered results
Merge pull request #3834 from ichord/gfm-autocomp

improve gfm autocomplete
Update CHANGELOG
Merge branch 'enhancement/issue_filter_dropdown' of /home/git/repositories/gitlab/gitlabhq
Dont show fork button in personal projects. Point to fork if already forked project
Fix project labels scope
Admin.user page: sort projects, add better confirm message for leaving team
Add extra config for some advanced customization
Add custom sing-in text & google analytics