The v0.9 release contains two new extensions, some improvements and bugfixes

A more detailed list of changes follows below. If you want to know the exact
and complete list of changes, you can check out the sources and check the logs.

Features:
* New extension: "External extensions", run external scripts
* New extension: "Firefox bookmarks", make firefox bookmarks acessible by albert
* Improvements on the VBox extension
* Several fixes. For details check the git log.
