fixed a bug that caused non-empty projects to appear empty in some cases

rotated two lines in lib/gitlab_git/repository.rb
the method `raw` needs @path_with_namespace,
so `raw.head.name` should not be executed before `@path_with_namespace = path_with_namespace`
Merge pull request #16 from origsun/master

fixed a bug that caused non-empty projects to appear empty in some cases