in publishing, fix an sbt 0.13 vs sbt 1 thing

version 1.2.0

first build on new 2.13-specific 1.2.x branch.
uses new 2.13 collections.
drops scala-xml dependency.

version 1.2.0-M2

M1 didn't publish

version 1.2.0-M1

testing whether removing scala-xml here gets the Scala 2.13
bootstrap script working again

Update Scala version to 2.13.0-M4-pre-20d3c21

Merge pull request #103 from lrytz/no-ant

Remove ant support

Merge pull request #100 from retronym/ticket/75-cleanup

Cleanups to new partest mode

Merge pull request #99 from retronym/ticket/75

Add a mode to reuse JVM for test execution

Merge pull request #98 from retronym/topic/selector

Pass the srcpath as FQN, test file as testSelector in SBT test events

Merge pull request #91 from som-snytt/issue/79-flags

Use readOptionFile and don't trim aggressively