varlociraptor/varlociraptor: Version 3.1.0

Generalized TMB plots to mutational burden plots (not tumor specific). Added a multi-sample variant using barplots (@jafors). Added testcase for and handling of missing CIGAR operation lenghts observations (@nh13, @dlaehnemann, @johanneskoester). Use hash map instead of BTree for managing event space. This should result in some speed-up (@johanneskoester). Fixed bugs with sex chromosome handling and prior distribution (@christopher-schroeder, @dawidkrzeciesa, @johanneskoester)