Fixed stackoverflow

This pull request has a couple of integration issues that have come up in Eclipse integration.  

25736dd - MobileSDKBuilder.build() method without the filter will just call itself again until stackoverflow.  This fix just points it to the other build() method.
34e37d8 - From Eclipse we need to able to invoke the mobile-sdk ant tasks but use the Eclipse java compiler instead of relying on user's JDK compiler in tools.jar