A fix for bug 1199945: AnalysisFeature title changed when analyser queue is busy.

https://bugs.launchpad.net/mixxx/+bug/1199945
Progress of the analyser queue is now visible from anywhere, via a change in the title from 'Analyze' to 'Analyze (x / y)' where x is the number of tracks that have been analyzed so far and y is the total number of tracks originally in the queue. This is an alternative to the progess bar images created by jus, as it allows for more detail in knowing how many tracks are left.