Fix redirection after sign in when using auto_sign_in_with_provider

Logic for redirect path moved to a filter. This allows it to run properly when the auto_sign_in_with_provider filter takes control.

See merge request !1146

Workaround the insecure password warnings emitted by MySQL 5.6

When using MySQL 5.6, the following output is emitted every time a backup is created, even with CRON=1.

```
Warning: Using a password on the command line interface can be insecure.
```

This fix works around that by sending the password via the [`MYSQL_PWD`](http://dev.mysql.com/doc/refman/5.6/en/environment-variables.html) environment variable.

See merge request !1139

Fix for #9527

Update Flowdock integration to support new Flowdock API

Requires that users create a Git source in their flows and update the configured token to the Git source token. The old flow tokens can't be used.

Disable internal issue tracker if external tracker in use

### What does this MR do?

This MR disables routes to the internal issue tracker if an external issue tracker (e.g. Redmine) is in use. A 404 page is returned if a user attempts to access any of the issue routes.

### Why was this MR needed?

Enabling the external issue tracker would still keep the internal one active, which would lead to odd behavior where users could create issues but not close them.

### What are the relevant issue numbers?

Closes #2006

See merge request !993

Set max-width for README, issue and merge request description

It allows easier text reading on big screens

### Problem

Text is hard to read on wide screens:

![Screenshot_2015-08-14_11.33.39](https://gitlab.com/gitlab-org/gitlab-ce/uploads/2bdb092c09495c7aa94b0589df4b7e65/Screenshot_2015-08-14_11.33.39.png)

### Solution

Set max-width to content. Screenshots:

![Screenshot_2015-08-14_11.31.54](https://gitlab.com/gitlab-org/gitlab-ce/uploads/00cd7a77b81b30458a1675ec562d7463/Screenshot_2015-08-14_11.31.54.png)
![Screenshot_2015-08-14_10.53.16](https://gitlab.com/gitlab-org/gitlab-ce/uploads/4756f87a3bbb7179e55b1c8f8ee40459/Screenshot_2015-08-14_10.53.16.png)
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

See merge request !1161

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

It allows easier text reading on big screens
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Fix: User search feature in admin area does not respect filters

https://dev.gitlab.org/gitlab/gitlabhq/issues/2482

See merge request !1155

Fix changelog

New doc about how to add an image in GitLab Basics

See merge request !1918

Time for 7.14.0.pre

Provide more feedback what went wrong if HipChat service failed test

This MR adds support for displaying the error message during HipChat service test. Before an Error 500 would be displayed with no helpful remarks.

Screenshot:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/10f82eb02db138f9680e69cdb3d3ed82/image.png)

Issue gitlab-com/support-forum#213

See merge request !1144

Bring clone bar back

Screenshot:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/5198a110c1f1bfd5b6b050b648e8ad45/image.png)

See discussion in !1080

See merge request !1147

Update changelog

See merge request !1153

Note query information

See merge request !1149

markup_helper: detect .mkd and .mkdn as markdown

See merge request !1148

This reverts commit 4c586dc7.

See discussion in !1080

Move merge manually text below merge widget 

Replace !1121 

Screenshot: 

#### Before

![Screenshot_2015-08-10_18.25.22](https://gitlab.com/gitlab-org/gitlab-ce/uploads/ac7df8dd03104b3b44c61b3bff709653/Screenshot_2015-08-10_18.25.22.png)


#### After

![Screenshot_2015-08-10_18.28.30](https://gitlab.com/gitlab-org/gitlab-ce/uploads/c92b8eaeadb842705577dba1f52b67e5/Screenshot_2015-08-10_18.28.30.png)



See merge request !1141

Logic for redirect path moved to a filter.

command line.

Issue gitlab-com/support-forum#213

Add merged label on branches page

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

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