update dojo submodules for rewritten(!) dojo repositories
make escape key clear the location box it if it focused, references #269
fix missing arrayCopy in BigWig/RequestWorker.  surprisingly, this fixes #261
fix `prepare-refseqs.pl` for use with Bio::DB::Das::BioSQL
fix small track selector bug, fixes #271
add a `trackSelector.initialSortColumn` configuration variable, fixes #270
fix arrowheads not always being visible while panning
Merge branch 'maint/1.9.x'