Collections in extension eve_settings now should start with the ext name.

Instead of Pillar automagically prepending 'attract.' or 'flamenco.' to the
names this should now be done explicitly in the extension's Eve settings.
This allows for more explicit configuration, and ensures foreign key
definitions are unambiguous.

pillar/__init__.py

@@ -225,11 +225,14 @@ class PillarServer(Eve):
         eve_settings = pillar_extension.eve_settings()
 
         if 'DOMAIN' in eve_settings:
+            pillar_ext_prefix = pillar_extension.name + '.'
             for key, collection in eve_settings['DOMAIN'].items():
-                source = '%s.%s' % (pillar_extension.name, key)
-                url = '%s/%s' % (pillar_extension.name, key)
+                assert key.startswith(pillar_ext_prefix), \
+                    'Eve collection names of %s MUST start with %r' % \
+                    (pillar_extension.name, pillar_ext_prefix)
+                url = key.replace('.', '/')
 
-                collection.setdefault('datasource', {}).setdefault('source', source)
+                collection.setdefault('datasource', {}).setdefault('source', key)
                 collection.setdefault('url', url)
 
             self.config['DOMAIN'].update(eve_settings['DOMAIN'])