Adding support for zLinux and PowerPC

The only changes were made in `binding.gyp`, just a couple of extra checks. It should not affect installation on the mainstream systems in any way. I've only been able to check it on Ubuntu 12.04, x86_64, but can't see why it would be different for any other OS.

For testing:
```
npm install CGavrila/node-java
```

Edit:
If there are any issues or concerns, please share.

Thank you,
Cristian