pidgin/pidgin

Port libpurple from purple_protocols_ to purple_protocol_manager_

Testing Done:
Compiled and ran locally.

Bugs closed: PIDGIN-17472

Reviewed at https://reviews.imfreedom.org/r/538/
REVIEWBOARD_URL = "https://reviews.imfreedom.org/"
REPOSITORY = "pidgin/pidgin"
REPOSITORY_TYPE = "mercurial"
BRANCH = "default"
LAND_DEST_BRANCH = "default"
LAND_PUSH = False