fix unsucessful parsing by using post-receive

Introduce new post-receive hook for scheduling
sidekiq jobs on push.
fix post-receive hook
re-use old git-hook structure, just add post-receive

The old working structure is used again, but with
the change, that update_redis is not called in
the update-hook. This must be called in the
post-receive-hook, which in turn should be safe
in terms of permission-handling.

The previous way of handling this was safe, so
we want stick to that.
Merge branch 'fix_push_but_no_ontologies2' into develop.ontohub.org

Conflicts:
	git/hooks/post-receive
	git/lib/git_update.rb