java13 - update to asm7.1 and doc java 13 compatibility

mvn.version - 2.0.1: bump version

scheduler - avoid using awaitQuiescence, not available in java 7

scheduler - numThreads, bugfix: predicate was reversed

mvn.version - 2.0.0-28 (unreleased): bump version

demos - consolidate demo poms

java11 - switch to Opcodes.ASM7_EXPERIMENTAL and visit nestmates with…

… ASM, ie JEP 181 support

mvn.deploy - automatic version tag: 2.0.0-20

mvn.deploy - automatic version tag: 2.0.0-19

java11 - switch to Opcodes.ASM7_EXPERIMENTAL