[#6535] ticket:417 controller for github import

Conflicts:
	ForgeImporters/forgeimporters/base.py
[#6535] ticket:417 basic github tickets import

Conflicts:
	ForgeImporters/forgeimporters/base.py
[#6535] ticket:417 github tickets import labels and attaches

Conflicts:
	ForgeImporters/forgeimporters/github/__init__.py
[#6535] ticket:417 rebased master and 42cc_6533
[#6535] ticket:317 github comments import

Conflicts:
	ForgeImporters/forgeimporters/github/__init__.py
[#6535] ticket:417 milestone processing added
[#6535] ticket:417 tests for github tracker import
[#6535] ticket:423 added regexp for project name
[#6535] ticket:423 fixed user link
[#6535] ticket:423 added exception handling
[#6535] ticket:423 fixed test
[#6535] ticket:423 Fix validator message
[#6535] ticket:425 Import tracker into existing project
[#6535] ticket:424 Handle pagination
[#6535] ticket:424 Fix exception due to ImportErrorHandler changes in 3c0a7e0f5fd179096d48239e3db8c014960a2181
[#6535] ticket:424 Fetch issue events from github
[#6535] ticket:424 Import events
[#6535] ticket:424 Refactoring: use self.parse_datetime everywhere
[#6535] ticket:424 Refactoring: use self.get_user_link everywhere
[#6535] ticket:424 Fix status names for tracker

Fixes default saved searches for closed and open ticket.