Merge pull request #17 from bpross-52n/master

Fixed a bug in ExecuteResponseBuilder, added more tests, cleaned up. 
There seems to be no discussion.
adjust poms: remove log4j, add slf4j+logback
add logback.xml, remove log4j.properties
adjust logger syntax to slf4j
Merge pull request #19 from matthesrieke/master

Migrate to SLF4J+Logback [v2]
Merge remote-tracking branch 'upstream/master'