plugins improvement

- new protocols field in plugins info, useful to know which ones are implemented by the plugin
- XEP-0153 first implementation (vcard avatars)
- plugin vcard: avatar & nick cached, clients are noticed of updated values

plugins/plugin_xep_0100.py

@@ -31,6 +31,7 @@ PLUGIN_INFO = {
 "name": "Gateways Plugin",
 "import_name": "XEP_0100",
 "type": "XEP",
+"protocols": ["XEP-0100"],
 "dependencies": ["XEP_0077"],
 "main": "XEP_0100",
 "description": """Implementation of Gateways protocol"""
@@ -79,7 +80,6 @@ class XEP_0100():
         """Look for items with disco protocol, and ask infos for each one"""
         #FIXME: target is used as we can't find the original iq node (parent is None)
         #       an other way would avoid this useless parameter (is there a way with wokkel ?)
-        
         if len(disco._items) == 0:
             debug ("No gateway found")
             self.host.actionResultExt(request_id,"DICT_DICT",{})