Specify pipe commands as arrays

This will be broken until there is an updated release of gitlab-grit,
which accepts arrays instead of strings to specify pipe_cmd.
less strict dependency rules

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

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Merge branch 'pipe_as_array'

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

Conflicts:
	lib/gitlab_git/repository.rb