Fix router functions check

When the router checks whether the requested route matches a function in the
functions list, it does not strip the extension, causing failures for URLs with extensions.
This change strips the extension before comparing to the list of functions.

gluon/rewrite.py

@@ -1040,7 +1040,7 @@ class MapUrlIn(object):
         else:
             default_function = self.router.default_function  # str or None
         default_function = self.domain_function or default_function
-        if not arg0 or functions and arg0 not in functions:
+        if not arg0 or functions and arg0.split('.')[0] not in functions:
             self.function = default_function or ""
             self.pop_arg_if(arg0 and self.function == arg0)
         else: