Enhance memorydb to load config.detectors and config.ext

Memorydb did not load the config.ini files from the tracker's
detectors and extensions directories. This caused an update to the
classic detectors (that used detectors/config.ini) to break testing.

Author: rouilj

test/memorydb.py

@@ -19,6 +19,8 @@
 
 def new_config(debug=False):
     config = configuration.CoreConfig()
+    config.detectors = configuration.UserConfig("share/roundup/templates/classic/detectors/config.ini")
+    config.ext = configuration.UserConfig("share/roundup/templates/classic/extensions/config.ini")
     config.DATABASE = "db"
     #config.logging = MockNull()
     # these TRACKER_WEB and MAIL_DOMAIN values are used in mailgw tests