hgweb: regenerate web substitutions when repo is refreshed

Previously, changes to the configuration would not be picked up by a
running server. That feels like a bug. Regenerate the web substitutions
table when the repository changes.

mercurial/hgweb/hgweb_mod.py

@@ -238,7 +238,6 b' class hgweb(object):'
         self.repostate = None
         self.mtime = -1
         self.reponame = name
-        self.websubtable = webutil.getwebsubs(r)
 
     def _getview(self, repo):
         """The 'web.view' config controls changeset filter to hgweb. Possible
@@ -280,6 +279,8 b' class hgweb(object):'
             # mtime is needed for ETag
             self.mtime = mtime
 
+            self.websubtable = webutil.getwebsubs(r)
+
     def run(self):
         """Start a server from CGI environment.