Grsecuirty - Ubuntu Kernel's .config Integration

I'm not 100% on how secure this this, but using your instructions without this step leaves our SecureDrop installation unable to decrypt our root partition. Anyway, I feel these instructions should include some support for encrypted partitions. Curious what you think about this pull request.

I added the part about rebooting the server so that the "uname -r" would work correctly. Seems like a good idea anyway.