Extract interface ResultNameStrategy and introduce impl ResultNameStrategyImpl
Extract ExpressionLanguageEngine from ResultNameStrategy
Allow to use your own ResultNameStrategy
Merge branch 'master' of https://github.com/jmxtrans/jmxtrans-agent

* 'master' of https://github.com/jmxtrans/jmxtrans-agent:
  Update README.md
  Update README.md
  Update README.md