ui: optionally ignore sub-options from configitems()

For convenience.

mercurial/ui.py

@@ -510,8 +510,14 b' class ui(object):'
         '''tell whether section exists in config.'''
         return section in self._data(untrusted)
 
-    def configitems(self, section, untrusted=False):
+    def configitems(self, section, untrusted=False, ignoresub=False):
         items = self._data(untrusted).items(section)
+        if ignoresub:
+            newitems = {}
+            for k, v in items:
+                if ':' not in k:
+                    newitems[k] = v
+            items = newitems.items()
         if self.debugflag and not untrusted and self._reportuntrusted:
             for k, v in self._ucfg.items(section):
                 if self._tcfg.get(section, k) != v: