Update merge request text to reflect editability of source/target branch

Screenshot 1 (source branch deleted):

![image](https://gitlab.com/gitlab-org/gitlab-ce/uploads/81dfbc4c790a1bb047d60cd4699bb71f/image.png)

Screenshot 2 (target branch deleted):

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/acec96c12d40175301ce4d4405137348/image.png)

Closes #2134

See merge request !1085

Added new doc about adding users and members

Added new doc in workflow about how to add users and members and I also linked it to "permissions".

See merge request !1916

Closes #2134

Bump redis-store to 1.1.6 and remove redis-store-fix-expiry

According to this https://github.com/redis-store/redis-store/compare/v1.1.4...v1.1.6 and my manual tests the monkey patch for redis-store is no longer required

/cc @jacobvosmaer @rspeicher 


See merge request !1081

Re-annotate models

Make `code` elements in links display as such

When a link consisted only of an inline code block -- ```[`like this`](https://google.com/)``` -- it was hard to tell that it was even a link.

Before:

> ![Screen_Shot_2015-07-31_at_5.45.06_PM](https://gitlab.com/gitlab-org/gitlab-ce/uploads/eda0a0630024d461c8de151d06e9f4db/Screen_Shot_2015-07-31_at_5.45.06_PM.png)

After:

> ![Screen_Shot_2015-07-31_at_5.43.15_PM](https://gitlab.com/gitlab-org/gitlab-ce/uploads/9542c49cfb4d43c015d464ef0ba0440f/Screen_Shot_2015-07-31_at_5.43.15_PM.png)


See merge request !1082

Also adds some minor padding to inline `code` elements.

Add ability to manage user email addresses via the API.

Addresses internal https://dev.gitlab.org/gitlab/gitlabhq/issues/2181

See merge request !1066

New doc about creating a Merge Request in GitLab Basics

Added new doc about creating a new branch.

See merge request !1917

Mention group and project names in flash messages upon create, update and delete.

Mention group and project names in flash messages upon create, update and delete. I also changed some wording inconsistency.

**Before**

![project_created](https://gitlab.com/axil/gitlab-ce/uploads/b91b92e46b08d6c566acee8d88fccff1/project_created.png)

**After**

![project_created_after](https://gitlab.com/axil/gitlab-ce/uploads/56db5125f2769386c43cf9e2f175a54d/project_created_after.png)

See merge request !1070

Add specific ability for managing group members

To be used for https://dev.gitlab.org/gitlab/gitlab-ee/issues/290 (Internal issue)

See merge request !1059

Fix multi-line syntax highlighting

### What does this MR do?

This MR fixes multi-line syntax highlighting in the code views. HTML span elements only apply to a single line, and in the case of multi-line comments, the highlighting was dropped as a result. Ensure that each line has
the proper styling to fix this.

### Why was this MR needed?

The current styling was broken for a while.

### Screenshots

Before:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/bbcb61760ab04a010aabc40942a2c0ba/image.png)

After:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/48f61c91b6fdd9c99cd7f3d214853141/image.png)

### What are the relevant issue numbers?

Closes #1577
Closes #1495

See merge request !1079

HTML span elements only apply to a single line, and in the case of multi-line
comments, the highlighting was dropped as a result. Ensure that each line has
the proper styling to fix this.

Closes #1577

Add spec to RelativeLinkFilter for Unicode filenames

Adds specs for changes added in !1050

See merge request !1078

Prepare Markdown feature spec for testing multiple pipelines

This MR lays the groundwork for including or excluding certain HTML::Pipeline
filters depending on what we're parsing. For example, excluding reference
filters in the Issues and Merge Requests titles.

See merge request !1053

Add project star and fork count, group avatar URL and user/group web URL attributes to API

Addresses internal https://dev.gitlab.org/gitlab/gitlabhq/issues/2521.

See merge request !1058

Update RelativeLinkFilter to support non-ASCII filenames

See merge request !1050