Add Hipchat services API
Merge branch 'hipchat_api' of https://github.com/qwazerty/gitlabhq into qwazerty-hipchat_api

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Conflicts:
	CHANGELOG
Merge branch 'qwazerty-hipchat_api' into 'master'

Add Hipchat services API

Manual merge of https://github.com/gitlabhq/gitlabhq/pull/7633

See merge request !1202
Merge branch 'master' of github.com:gitlabhq/gitlabhq

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Conflicts:
	CHANGELOG