Clean up XUL prefpane a bit
Remove outdated plugins
Add more logging
Make acFactory.test accept a url (spec) string
Expander: Remove complicated and hacky positioning code...

... does not work anymore with dta-3
Make build_plugins.py bail on error
Finally enable imagefap

... was disabled before as the only (experimental) sandbox plugin
Expander should carry over isPrivate
Massive plugin update + some additions

Closes GH-58
Closed GH-23
Implement "namer" property for resolver/expander/sandbox

Closes GH-24
Fix compart: Logger and getUsableFileName