Enhancement #31 and #32: Updated GWASGeneViewer version to 0..13-SNAPSHOT

New GWASGeneViewer version uses MAF as default filter value and exposes
setters to programatically set minMAC and minMAF filters.
Furthermore clients can add an EventHandler to react to changes in the filter.
Enhancement #31: Support for global MAF/MAC filter added

When the user changes the MAF/MAC slider of one chromosome also the other
chromosomes will be filtered. There is currently  no option to disable this
 functionality.