Implement IO::Socket::Async.bytes_supply
Add IO/Socket/Async.pm to JVM build. Bump setting build heap to 1000m for Java 8.
Bump NQP version to get async io ops on JVM.
Merge pull request #266 from donaldh/jvm_async_ops

Implement IO::Socket::Async.bytes_supply and bump NQP_REVISION to get async ops on JVM.