hooks: better error reporting for hooks module errors

vcsserver/hooks.py

@@ -173,7 +173,12 b' def _get_hooks_client(extras):'
     elif is_shadow_repo:
         return HooksShadowRepoClient()
     else:
-        return HooksDummyClient(extras['hooks_module'])
+        try:
+            import_module = extras['hooks_module']
+        except KeyError:
+            log.error('Failed to get "hooks_module" from extras: %s', extras)
+            raise
+        return HooksDummyClient(import_module)
 
 
 def _call_hook(hook_name, extras, writer):

vcsserver/remote/svn_remote.py

@@ -186,7 +186,6 b' class SvnRemote(RemoteBase):'
         # NOTE(marcink):  short circuit the check for SVN repo
         # the repos.open might be expensive to check, but we have one cheap
         # pre condition that we can use, to check for 'format' file
-
         if not os.path.isfile(os.path.join(path, 'format')):
             return False