Backup cron mode

If you have your server configured to receive emails containing the output of
cron jobs it is annoying to get long spammy emails from the backup script. This
change adds a 'cron mode' that makes the backup script silent unless something
goes wrong during the backup.

See merge request !1268

Add missing timestamps to the 'members' table

In 20140914145549_migrate_to_new_members_model.rb we forgot to set the
created_at and updated_at times for new records in the 'members' table. This
became a problem after commit c8e78d97 which
was added in GitLab 7.5. With this migration we ensure that all rows in
'members' have at least some created_at and updated_at timestamp.

See merge request !1272

Possibility to create Milestones or Labels when Issues are disabled

https://dev.gitlab.org/gitlab/gitlabhq/issues/1682

See merge request !1270

Add GitLab shell update to update guide

See merge request !1269

Rebuild keys

This was clearly lacking for the documenation.

See merge request !1267

Improve mobile UI. pt1

Related to #1493

* [x] App Header
* [x] Dashboard
* [x] Project home page

See merge request !1266

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Increase font size

Increase markdown typography font size to 15px.

Affected:

* wiki
* issue/mr description
* md files
* comments

Fixes #1662

See merge request !1265

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Small improvement to /api/user/keys docs

Hide gpg signature

Fixes #1743

See merge request !1263

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Bump gitlab git

See merge request !1261

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Fix tests

See merge request !1262

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

This reverts commit 533f4cdf.

Web edit and HTTPS push work if multiple Rubies installed v2

The keys resource includes a create_at attribute

Fork to group

Fixes #1592

* project can be forked into group
* fork link always lead to fork page where you select namespace where to fork

See merge request !1253

Before this it would fail because git hooks automatically prepend
things to the path, which can lead the wrong Ruby version to be called
in which dependencies are not installed.

To make sure that this is correct, the forked_merge_requests commented
out test that depends on this change was uncommented.

For that test to pass, it is also necessary to setup the mock server
on port 3001 under test_env.rb.

Updated documentation for 7.5 release

Documentation for 7.5 release has been updated. Changes include:

- Pointed Ruby version in guides to 2.1.5
- Pointed gitlab-shell version in guides to 2.2.0

See merge request !1259

Signed-off-by: NDmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Conflicts:
	CHANGELOG

Update changelog

See merge request !1258

remove duplicate time zone entry in CHANGELOG

fix backup rake task