Simplify test runner by adding a new option '--mayan-apps' that

automatically tests all Mayan apps that report to have tests.
Change the app flag that indicates when an app has test
from 'test' to the more explicit 'has_test'.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/smart_settings/apps.py

@@ -13,8 +13,8 @@ from .widgets import setting_widget
 class SmartSettingsApp(MayanAppConfig):
     app_namespace = 'settings'
     app_url = 'settings'
+    has_tests = True
     name = 'smart_settings'
-    test = True
     verbose_name = _('Smart settings')
 
     def ready(self):