security: added missing csrf checks in few missing views.

security: fixed self-xss inside file views.

security: fix self-xss inside repo strip view.

docs: added example how to secure login page from brute force attacks.

audit-logs: implemented pull request and comment events.

audit-logs: use specific web/api calls. - also normalized action_data to specs.

audit-logs: added audit logs on user groups admin page.

action_logger: removed really not required actions of start/stop following a repository. - this information just spams user information, and for product such as rhodecode this doesn't make any sense to be stored.

audit-logs: moved async tasks from old deprecated action_logger.

audit-logs: fill in some default values for the expected action data.