1) In standalone, now stops all components, if one fails. JIRA issue has been opened to restart runnables if they fail: https://issues.cask.co/browse/CDAP-477
2) Validate the handlers that user passes in during deploy time.
3) Move construction of NettyHttpServer to constructor of ServiceHttpServer (from startup)
4) Add a small test case to test (2).
addHandler() only adds to a list, and the specifications are generated at the end.
Merge branch 'develop' into feature/stop-service-upon-failure

Conflicts:
	cdap-app-fabric/src/main/java/co/cask/cdap/internal/app/services/DefaultServiceConfigurer.java
address comments - code cleanup, better log and error messages.
Merge pull request #559 from caskdata/feature/stop-service-upon-failure

CDAP-471 - Validate Service Handlers during deploy time.