Initial changes in support of a basic permissions set of services.
This includes a new approach to extension modules.
Adopt the new migrate module in migrating GGRC and its extensions
through the db_* commands.
Merge branch 'develop' into feature/roles_and_permissions
Change 'System URL' to 'Direct URL' on System/Process form
alteration of default grid values
gutter removed
sorting out paddings
Fixes and implementation of roles and user_roles services.
Eliminate obsolete drop of table from migration.
Fixes for permissions lookup and checking.
Merge pull request #55 from reciprocity/feature/change-system-url-to-direct-url

Change System URL to Direct URL
Create barebones prototype
Set revison.content type to TEXT
Migrate events.http_method datatype to enum

Clean up tab spacing to 2 chars
Remove redundant setting of created_at as it is handled by the
framework
Fix typo in migration comment and filename
Merge migrations into 1 file

This prevents unnecessary tweaking of down_revisions when the
merge with development takes time
Extension behave tests can reuse steps from ggrc and can be run using
ggrc.migrate module as a command. For example:
  python -m ggrc.migrate ggrc_basic_permissions/service_specs
However, it is necessary to set the GGRC_SETTINGS_MODULE environment
variable to pickup the required settings modules.
delete renamed module.
Merge branch 'develop' into feature/roles_and_permissions
Added context_id to events and revisions