Move `LfsHelper` methods somewhere else than `app/helpers`
app/helpers
is meant to contain views helpers but LfsHelper
is actually used as a simple module included in Projects::LfsApiController
& Projects::LfsStorageController
.
Since both inherits from Projects::GitHttpClientController
, we could just move the helper methods back to this controller, or even create a controller concern for that.
/cc @ayufan (https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5735/diffs#note_15510471)