Foren / Cotonti / Extensions / [Release] Widgets

Some sites run off the trunk, so why not? Also it's good to be prepared and have some plugins ready before the release, and Siena-only plugins can help people make the decision to upgrade.

Actually we've been creating a lot of plugins for Siena, because many core features are moved out of core into a plugin. For example the hidden groups and user avatar/photo are now in plugins.