Cleanup and refactor release doc. Follow issue as a todo list

doc/release/howto_rc1.md

+# How to create RC1
+
+The RC1 release comes with the task to update the installation and upgrade docs. Be mindful that there might already be merge requests for this on GitLab or GitHub.
+
+### **1. Update the installation guide**
+
+1. Check if it references the correct branch `x-x-stable` (doesn't exist yet, but that is okay)
+1. Check the [GitLab Shell version](/lib/tasks/gitlab/check.rake#L782)
+1. Check the [Git version](/lib/tasks/gitlab/check.rake#L794)
+1. There might be other changes. Ask around.
+
+### **2. Create update guides**
+
+1. Create: CE update guide from previous version. Like `7.3-to-7.4.md`
+1. Create: CE to EE update guide in EE repository for latest version.
+1. Update: `6.x-or-7.x-to-7.x.md` to latest version.
+1. Create: CI update guide from previous version
+
+It's best to copy paste the previous guide and make changes where necessary.
+The typical steps are listed below with any points you should specifically look at.
+
+#### 0. Any major changes?
+
+List any major changes here, so the user is aware of them before starting to upgrade. For instance:
+
+- Database updates
+- Web server changes
+- File structure changes
+
+#### 1. Stop server
+
+#### 2. Make backup
+
+#### 3. Do users need to update dependencies like `git`?
+
+- Check if the [GitLab Shell version](/lib/tasks/gitlab/check.rake#L782) changed since the last release.
+
+- Check if the [Git version](/lib/tasks/gitlab/check.rake#L794) changed since the last release.
+
+#### 4. Get latest code
+
+#### 5. Does GitLab shell need to be updated?
+
+#### 6. Install libs, migrations, etc.
+
+#### 7. Any config files updated since last release?
+
+Check if any of these changed since last release:
+
+- [lib/support/nginx/gitlab](/lib/support/nginx/gitlab)
+- [lib/support/nginx/gitlab-ssl](/lib/support/nginx/gitlab-ssl)
+- <https://gitlab.com/gitlab-org/gitlab-shell/commits/master/config.yml.example>
+- [config/gitlab.yml.example](/config/gitlab.yml.example)
+- [config/unicorn.rb.example](/config/unicorn.rb.example)
+- [config/database.yml.mysql](/config/database.yml.mysql)
+- [config/database.yml.postgresql](/config/database.yml.postgresql)
+- [config/initializers/rack_attack.rb.example](/config/initializers/rack_attack.rb.example)
+- [config/resque.yml.example](/config/resque.yml.example)
+
+#### 8. Need to update init script?
+
+Check if the `init.d/gitlab` script changed since last release: [lib/support/init.d/gitlab](/lib/support/init.d/gitlab)
+
+#### 9. Start application
+
+#### 10. Check application status
+
+### **3. Code quality indicators**
+
+Make sure the code quality indicators are green / good.
+
+- [![Build status](http://ci.gitlab.org/projects/1/status.png?ref=master)](http://ci.gitlab.org/projects/1?ref=master) on ci.gitlab.org (master branch)
+
+- [![Build Status](https://semaphoreapp.com/api/v1/projects/2f1a5809-418b-4cc2-a1f4-819607579fe7/243338/badge.png)](https://semaphoreapp.com/gitlabhq/gitlabhq) (master branch)
+
+- [![Code Climate](https://codeclimate.com/github/gitlabhq/gitlabhq.png)](https://codeclimate.com/github/gitlabhq/gitlabhq)
+
+- [![Dependency Status](https://gemnasium.com/gitlabhq/gitlabhq.png)](https://gemnasium.com/gitlabhq/gitlabhq) this button can be yellow (small updates are available) but must not be red (a security fix or an important update is available)
+
+- [![Coverage Status](https://coveralls.io/repos/gitlabhq/gitlabhq/badge.png?branch=master)](https://coveralls.io/r/gitlabhq/gitlabhq)
+
+### 4. Run release tool for CE and EE
+
+**Make sure EE `master` has latest changes from CE `master`**
+
+Get release tools
+
+```
+git clone git@dev.gitlab.org:gitlab/release-tools.git
+cd release-tools
+```
+
+Release candidate creates stable branch from master. 
+So we need to sync master branch between all CE remotes. Also do same for EE.
+
+```
+bundle exec rake sync
+```
+
+Create release candidate and stable branch:
+
+```
+bundle exec rake release["x.x.0.rc1"]
+```
+
+Now developers can use master for merging new features.
+So you should use stable branch for future code chages related to release.
+
+
+### 5. Release GitLab CI RC1
+
+Add to your local `gitlab-ci/.git/config`:
+
+```
+[remote "public"]
+    url = none
+    pushurl = git@dev.gitlab.org:gitlab/gitlab-ci.git
+    pushurl = git@gitlab.com:gitlab-org/gitlab-ci.git
+    pushurl = git@github.com:gitlabhq/gitlab-ci.git
+```
+
+* Create a stable branch `x-y-stable`
+* Bump VERSION to `x.y.0.rc1`
+* `git tag -a v$(cat VERSION) -m "Version $(cat VERSION)"
+* `git push public x-y-stable v$(cat VERSION)`
+