Update ASM to 4.2, fix for issue #138

Updated ASM dependency from 4.1 to 4.2, to prevent issues with Groovy inner classes.

ASM issue: 316380 Bug in org.objectweb.asm.util.CheckClassAdapter.visitInnerClass() regarding inner class name. http://forge.ow2.org/tracker/index.php?func=detail&aid=316380&group_id=23&atid=100023