Build RPMs

Hi, 

I don't know whether it's on your roadmap to package the driver - but I needed this, so I've done it.  

I've used CPack.  Per the changes in the README - which, come to think of it, you wouldn't want to take - I've tested this only on CentOS 6.5, and have successfully produced both 32-bit and 64-bit RPMs.

If this work's useful to you you're welcome it - indeed I'd be glad not to have to maintain these tweaks myself.  But if not then that's just fine.