Bugfix Git ident id

cps/web.py

@@ -714,6 +714,7 @@ def get_tags_json():
 def get_update_status():
     status = {}
     if request.method == "GET":
+        # should be automatically replaced by git with current commit hash
         commit_id = '$Id$'
         commit = requests.get('https://api.github.com/repos/janeczku/calibre-web/git/refs/heads/master').json()
         if "object" in commit and commit['object']['sha'] != commit_id[5:-2]: