- dynamic loading for parsing modules

- add RSSCloud support (http://rsscloud.org)
- add XOXO parser (http://microformats.org/wiki/xoxo)
- add XBEL parser (http://pyxml.sourceforge.net/topics/xbel/)

- namespace OpenSearch (http://a9.com/-/spec/opensearchrss/1.0/)

- add implementation of PubSubHubBub publisher
- use libedataserver/EAccount to describe people found in feeds
- use libchamplain/ChamplainPoint to describe GeoRSS coordinates
