Update 7-13-stable with 7.13.4



See merge request !230

Update 7-13-stable (7.13.1)



See merge request !166

- check if user has manage access to project
- don't cache result of authorized_projects, because it's serialised with User object
- clear user sessions

Create config/secrets.yml with 0600

See merge request !200

Update install and update documentation for 7.13

@JobV Please push directly to this branch and merge if ok.

See merge request !199

Allow to specify flexible list of types in yaml

First part of flexible pipeline build in GitLab CI

Having following `.gitlab-ci.yml`:
```
types:
- test
- deploy
- notify

rspec:
  script: "rspec"

rubocop:
  script: "rubocop"

staging:
  type: deploy
  script: "echo deploy"
  only:
  - master

production:
  type: deploy
  script: "echo production"
  only:
  - tags

dockerhub:
  type: notify
  script: "curl http://docker/hub/web/hook"

downstream:
  type: notify
  script: "curl http://build/downstream/jobs"
```

GitLab CI will trigger two test jobs in parallel, when finished it will trigged either staging or production, when finished it will trigger dockerhub and downstream in parallel.

The UI (screenshots are not for above YAML):
![Screen_Shot_2015-07-10_at_15.56.26](https://gitlab.com/gitlab-org/gitlab-ci/uploads/1f714b73772cf0d44168fb8e20e35561/Screen_Shot_2015-07-10_at_15.56.26.png)
![Screen_Shot_2015-07-10_at_15.57.19](https://gitlab.com/gitlab-org/gitlab-ci/uploads/fc9f458f2ca517d923a4382466fa99eb/Screen_Shot_2015-07-10_at_15.57.19.png)

TODO:
- [x] Implement in CI
- [x] Specs
- [x] Changelog
- [x] CI tests
- [ ] Documentation

/cc @vsizov @sytses @dzaporozhets

See merge request !198

Encrypt variables

/cc @dzaporozhets @jacobvosmaer @vsizov

See merge request !187

Use config/secrets.yml to store session secret and database encryption secret

I took the approach that config/secrets.yml is generated when key is not found.

/cc @vsizov @jacobvosmaer

See merge request !195

```
types:
- test
- deploy
- notify

rspec:
  script: "rspec"

rubocop:
  script: "rubocop"

staging:
  type: deploy
  script: "echo deploy"
  only:
  - master

production:
  type: deploy
  script: "echo production"
  only:
  - tags

dockerhub:
  type: notify
  script: "curl http://docker/hub/web/hook"

downstream:
  type: notify
  script: "curl http://build/downstream/jobs"
```

This will trigger two test jobs in parallel, when finished it will trigged either staging or production, when finished it will trigger dockerhub and downstream in parallel.

Use builds_without_retry to calculate average coverage

/cc @vsizov

See merge request !197

Disable link to runner if it's not assigned to specific project

Fixes 404 when clicking on available runner from project's page

/cc @vsizov

See merge request !196