Merge pull request #17 from sdalton1/master

Generalized SA coarse solver interface
Merge pull request #18 from sdalton1/master

Added CR method
Merge pull request #21 from sdalton1/master

Silenced CUDA 5.0 warnings
Fixed compatiability with CUDA 4.2 resolves #19
Added interface to return roots of SA aggregates
Addressed minor warnings
Added compile time check for correct support for hilbert curve example
Reverted to previous hilbert version