disq-0.3.2

This is a minor release which fixes several bugs ( #108, #109, #110 ).

As of this release we now test Disq on Java 11. Java 11 support should be considered beta since spark doesn't officially support Java 11 yet.

Complete change list:
11eb512 Don't merge empty part files. Fixes #110 (#111)
4bb4334 Test on Java 11 (#106)
03339e2 BAI merge for hg38 fails with OOM (#109)
948ed61 Cannot merge tabix files with different sequence names (#108)
52649fd Parameterize Scala version (#94)
8e45fc3 Reduce warning to info on unsupported concat operation. (#104)