Update clang reference version to a recent 3.6dev

Summary:
Update clang reference version to a recent 3.6dev

Updated docs and archive. Applied a minimal set of changes to fix compilation.

Test Plan: make test

Reviewers: yiding

Reviewed By: yiding

Subscribers: irene, mathieubaudet, dulmarod

Differential Revision: https://phabricator.fb.com/D1554232

Tasks: 5134636
Remove obsolete checker DoubleBooleanArgumentChecker.cpp

Summary:
Remove obsolete checker DoubleBooleanArgumentChecker.cpp

This checker is superseded by alpha.core.IdenticalExpr.

Test Plan: make test

Reviewers: yiding

Reviewed By: yiding

Differential Revision: https://phabricator.fb.com/D1554236

Tasks: 5134636