Break config_default into master_site_configs.

masters/master.client.sfntly/master.cfg

 # -*- Python -*-
 # ex: set syntax=python:
 
 # This is a sample buildmaster config file. It must be installed as
 # 'master.cfg' in your buildmaster's base directory.
 
 import config
+import master_site_config
 
 # This is the dictionary that the buildmaster pays attention to. We also use
 # a shorter alias to save typing.
 c = BuildmasterConfig = {}
 
 ####### CHANGESOURCES
 
 # the 'change_source' setting tells the buildmaster how it should find out
 # about source code changes.  Here we point to the buildbot clone of pyflakes.
 
@@ skipping 254 matching lines @@
 c['schedulers'] = [
     SingleBranchScheduler(
         name="all",
         branch=None,
         treeStableTimer=30,
         builderNames=allBuilders)
 ]
 
 ####### BUILDSLAVES
 
-ActiveMaster = config.Master.Sfntly
+ActiveMaster = master_site_config.Sfntly
 
 # The 'slaves' list defines the set of allowable buildslaves. List all the
 # slaves registered to a builder. Remove dupes.
 c['slaves'] = master_utils.AutoSetupSlaves(c['builders'],
                                            config.Master.GetBotPassword())
 
 # Make sure everything works together.
 master_utils.VerifySetup(c, slaves)
 
-ActiveMaster = config.Master.Sfntly
+ActiveMaster = master_site_config.Sfntly
 c['projectName'] = ActiveMaster.project_name
 c['projectURL'] = ActiveMaster.project_url
 c['buildbotURL'] = 'http://build.chromium.org/p/client.sfntly/'
 
 # Adds common status and tools to this master.
 master_utils.AutoSetupMaster(c, ActiveMaster)
 
 ####### DB URL
 
 # This specifies what database buildbot uses to store change and scheduler
 # state.  You can leave this at its default for all but the largest
 # installations.
 c['db_url'] = "sqlite:///state.sqlite"