pidgin/pidgin

Add a settings property to PurpleCredentialProvider that is a GSettings object

Testing Done:
Ran the unit tests. However I didn't add this to the tests because adding a dummy settings object is more trouble than it's worth.

Reviewed at https://reviews.imfreedom.org/r/2145/
REVIEWBOARD_URL = "https://reviews.imfreedom.org/"
REPOSITORY = "pidgin/pidgin"
REPOSITORY_TYPE = "mercurial"
BRANCH = "default"
LAND_DEST_BRANCH = "default"
LAND_PUSH = False