Replaces vue resource with axios for environments code
EE port of https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/18950
Also removes unsued code to reduce https://gitlab.com/gitlab-org/gitlab-ee/issues/5845
EE port of https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/18950
Also removes unsued code to reduce https://gitlab.com/gitlab-org/gitlab-ee/issues/5845