Feature/repair travis

Made travis ci working again. Test are run against local install of gitlab 7-2-stable branch. The scripts prepare_test_env.sh and install_gitlab.sh could be used to provision local vm's to run tests against. I had to deactivate some tests since there was no clear setup tear down strategy nor commits to newly created projects.

Additionally mage some changes to the api, hopefully without breaking any compability with older versions.
- login allows now logins with either username or email address. (Was limited to mail address)
- createproject now has namespace optional (aligned with gitlab api which refers name as only required argument)