Merge branch 'users_permissions' into 'master'

Add user permissions matrix

https://dev.gitlab.org/gitlab/gitlab-ci/issues/127

# Users Permissions

GitLab CI relies on user's role on the GitLab. There are three permissions levels on GitLab CI: admin, master, developer, other.

Admin user can perform any actions on GitLab CI in scope of instance and project. Also user with admin permission can use admin interface.

| Action                                | Guest, Reporter | Developer   | Master   | Admin  |
|---------------------------------------|-----------------|-------------|----------|--------|
| See commits and builds                | ✓               | ✓           | ✓        | ✓      |
| Retry or cancel build                 |                 | ✓           | ✓        | ✓      |
| Remove project                        |                 |             | ✓        | ✓      |
| Create project                        |                 |             | ✓        | ✓      |
| Change project configuration          |                 |             | ✓        | ✓      |
| Add specific runners                  |                 |             | ✓        | ✓      |
| Add shared runners                    |                 |             |          | ✓      |
| See events in the system              |                 |             |          | ✓      |
| Admin interface                       |                 |             |          | ✓      |

See merge request !93

doc/README.md

@@ -5,4 +5,5 @@
 + [Install](install/installation.md)
 + [Update](update/README.md)
 + [Jobs](jobs/README.md)
-+ [Runners](runners/README.md)
\ No newline at end of file
++ [Runners](runners/README.md)
++ [Permissions](permissions/README.md)

doc/permissions/README.md

+# Users Permissions
+
+GitLab CI relies on user's role on the GitLab. There are three permissions levels on GitLab CI: admin, master, developer, other.
+
+Admin user can perform any actions on GitLab CI in scope of instance and project. Also user with admin permission can use admin interface.
+
+
+
+
+| Action                                | Guest, Reporter | Developer   | Master   | Admin  |
+|---------------------------------------|-----------------|-------------|----------|--------|
+| See commits and builds                | ✓               | ✓           | ✓        | ✓      |
+| Retry or cancel build                 |                 | ✓           | ✓        | ✓      |
+| Remove project                        |                 |             | ✓        | ✓      |
+| Create project                        |                 |             | ✓        | ✓      |
+| Change project configuration          |                 |             | ✓        | ✓      |
+| Add specific runners                  |                 |             | ✓        | ✓      |
+| Add shared runners                    |                 |             |          | ✓      |
+| See events in the system              |                 |             |          | ✓      |
+| Admin interface                       |                 |             |          | ✓      |
+
+
+
+