Expose the plugin manager from the node.
Refactor list of official plugins into an own class.
Update plugins to the latest versions.
Merge branch 'next' into official-plugins-refactoring

Conflicts:
	src/freenet/pluginmanager/PluginManager.java
Update FlogHelper key to v32.
Merge pull request #212 from Bombe/official-plugins-refactoring

Official plugins refactoring