=pro,ben update sbt-jmh to 0.1.4 (provides JMH 0.9 (latest))

Updates JMH to latest version; 
Mostly internal cleanups, but also changed default bytecode generator (reflection, instead of asm) - should handle edgy cases better.

Changelog: http://hg.openjdk.java.net/code-tools/jmh/

TODO: 
- [ ] forward port to master and 2.3-dev