Add description to activity palette
completed by: Ignacio Rodríguez
mentors: Walter Bender
As per http://wiki.sugarlabs.org/go/File:Journal-04.jpeg and http://wiki.sugarlabs.org/go/Design_Team/Designs/Journal (No. 4) add a few lines of the activity description to the palette in the journal listview. If the description is bkank, leave it out; if it is long, use ellipsis.
Also see http://bugs.sugarlabs.org/ticket/4686