Enable the kotlin-annotation-processing plugin and pass annotation
processors to it.
Bug: 122251693
Test: m checkbuild
Test: TestKapt in kotlin_test.go
Change-Id: I841df454beaaa7edd263eea714ca0d958a03c9de
kapt is going to make kotlin a little more complicated, move the
rules and tests to their own files.
Bug: 122251693
Test: m checkbuild
Change-Id: Ieed78b97995ced210b710bd50c357514cc8e3bc6