gitmanager: lowercase compare for GH error msgs. --autopull

This way, we don't have to worry about mistyping the upper or lowercase characters incorrectly, and we can explicitly only worry about content.  I don't trust *not* making a mistake there with case of character, so let's do the lowercase comparison instead.

Also, got annoyed about the wavy lines on DeletionWatcher's class methods, so add a suppression for those warnings and inspections in IDEs.  It was so minor a change it didn't warrant its own commit.

deletionwatcher.py

@@ -9,7 +9,7 @@
 import datahandling
 
 
-# noinspection PyClassHasNoInit,PyBroadException
+# noinspection PyClassHasNoInit,PyBroadException,PyMethodParameters
 class DeletionWatcher:
     @classmethod
     def update_site_id_list(self):

gitmanager.py

@@ -89,7 +89,7 @@ def add_to_blacklist(**kwargs):
                 return (True, "You don't have code privileges, but I've [created a pull request for you]({0}).".format(response.json()["html_url"]))
             except KeyError:
                 # Error capture/checking for any "invalid" GH reply without an 'html_url' item, which will throw a KeyError.
-                if "Bad credentials" in str(response.json()['message']):
+                if "bad credentials" in str(response.json()['message']).lower():
                     # Capture the case when GH credentials are bad or invalid
                     return (False, "Something is wrong with the GH credentials, tell someone to check them.")
                 else: