remote-hg: add shared repo upgrade

If we have an old organization (v1.8.3), and want to upgrade to a newer
one (v1.8.4), the user would have to fetch the whole repository, instead
we can just move the repository, so the user would not notice any
difference.

Also, remove other clones, so in time they get set up as shared.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Reviewed-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/remote-helpers/git-remote-hg

@@ -392,6 +392,18 @@ def get_repo(url, alias):
     else:
         shared_path = os.path.join(gitdir, 'hg')
 
+        # check and upgrade old organization
+        hg_path = os.path.join(shared_path, '.hg')
+        if os.path.exists(shared_path) and not os.path.exists(hg_path):
+            repos = os.listdir(shared_path)
+            for x in repos:
+                local_hg = os.path.join(shared_path, x, 'clone', '.hg')
+                if not os.path.exists(local_hg):
+                    continue
+                if not os.path.exists(hg_path):
+                    shutil.move(local_hg, hg_path)
+                shutil.rmtree(os.path.join(shared_path, x, 'clone'))
+
         # setup shared repo (if not there)
         try:
             hg.peer(myui, {}, shared_path, create=True)