Patch to support excludegroups in TestNG

I have a very small patch for supporting excludegroups in TestNG (something we desperately need in order to move from Maven to Builder). Passing the excludegroups via :properties does not work as this param is not meant to be a -D arg (which is how it seems all the key/value pairs in properties are added), but is a command line argument to org.testng.TestNG. I could not find if there were anyone else who had solved this issue or if there was a JIRA -- so I assumed it just hadn't come up yet. This should probably be extended to support all the options for running TestNG (http://testng.org/doc/documentation-main.html#running-testng), but this was by far the most necessary for our needs. If deemed OK, I'd be willing to add support for all the options in a similar manner. Thanks.