ApplicationSetting.current was called in every pages, cache it and expires it after it updated.

This changes will avoid a SQL query in every pages (~0.3 - 0.5ms).

```SQL
SELECT  "application_settings".* FROM "application_settings"   ORDER BY "application_settings"."id" DESC LIMIT 1
```

[ci skip]

Fix duplicate entry for 8.1.0 release

Fix Drone CI service template not saving properly

This fixes an Error 500 when attempting to save a Drone CI template in the service template page. `hook.url` was not being used and depended upon a project when none existed.

/cc: @bugagazavr

Closes #3419

See merge request !1774

Closes #3419

Remove text-rendering property

Continues !1779

Closes #3220

[ci skip]

See merge request !1784

Closes #3220

[ci skip]

Replace CoffeeScript block into JavaScript in Views.

Remove CSS property preventing hard tabs from rendering in Chromium 45

This is to workaround a bug in Chromium 45 (https://code.google.com/p/chromium/issues/detail?id=446434),
which is the default browser in Ubuntu 14.04 and older.

Closes #3220

See merge request !1779

Remove duplicate CHANGELOG etnries

[ci skip]

See merge request !1782

[ci skip]

Bump rugged version to be in line with gitlab_git requirements



See merge request !1780

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

This is to workaround a bug in Chromium 45 (https://code.google.com/p/chromium/issues/detail?id=446434),
which is the default browser in Ubuntu 14.04 and older.

Closes #3220

Display target branch on MR list when it is different from project's default

Fixes #3072

The screenshot below shows both previous and current UI state:

![branch-mr-both](/uploads/5c1f0519e42bae4655f3eee37edfc356/branch-mr-both.png)

First merge request has default branch as a target, second one has non default branch as target.

See merge request !1741

Switch to state_machines-activerecord (Fixes: #3374)

state_machine is unmaintained

See merge request !1764

For example view: shared/issuable/_context

CoffeeScript: 190ms
JavaScript: 19.7ms

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

* fix commit duration graph
* make graphs responsive
* fix wrong padding
* add a bit of explanation to colors
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Fix duplicate entry for 8.1.0 release and remove unreleased tag.

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

Change documentation of converting a MySQL-Database to a Postgres one

The instructions were missleading. See -> https://gitlab.com/gitlab-org/gitlab-ce/issues/2904

closes #2904

See merge request !1549

[ci skip]

[ci skip]

Fix incoming email config defaults

Fixes #3377.

See merge request !1766

Switch back to github-linguist

Merge button has color from CI status

This MR closes #3313

I'am not realy sure about the color for the skipped status (red)...

UI changes:

![accpet-mr-ci-failed](/uploads/c03970c468b89e38ed2c5e3171f53505/accpet-mr-ci-failed.png)

![accpet-mr-ci-skipped](/uploads/f29cbc69e77cc95b33522135b327cc51/accpet-mr-ci-skipped.png)

![accpet-mr-ci-pending](/uploads/79612a66fd497174e00bd348c9cba69c/accpet-mr-ci-pending.png)

![accpet-mr-ci-success](/uploads/4b601e6d02b860db5ff53c47c98f3206/accpet-mr-ci-success.png)


See merge request !1761

This ensures the application can still boot when the "development" group
is not available.

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

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

See merge request !1749