Autoadmin: Incorporate the autoadmin app

Incorporate the external django-autoadmin app as a core app
and convert it into a Mayan app. This change adds the new
settings: "COMMON_AUTOADMIN_EMAIL", "AUTOADMIN_PASSWORD", and
"AUTOADMIN_USERNAME".

Signed-off-by: Roberto Rosario <Roberto.Rosario@mayan-edms.com>

mayan/apps/autoadmin/apps.py

@@ -0,0 +1,23 @@
+from __future__ import unicode_literals
+
+from django.conf import settings
+from django.db.models.signals import post_save
+from django.utils.translation import ugettext_lazy as _
+
+from mayan.apps.common import MayanAppConfig
+
+from .handlers import handler_auto_admin_account_password_change
+
+
+class AutoAdminAppConfig(MayanAppConfig):
+    has_tests = True
+    name = 'mayan.apps.autoadmin'
+    verbose_name = _('Auto administrator')
+
+    def ready(self):
+        super(AutoAdminAppConfig, self).ready()
+        post_save.connect(
+            dispatch_uid='auto_admin_account_password_change',
+            receiver=handler_auto_admin_account_password_change,
+            sender=settings.AUTH_USER_MODEL
+        )