Import utilities
Add test for exception
Add CUFFT_ERROR
Add fft2d::{r2c,c2r}
Make fft2d::{r2c,c2r} inline
Add test (still moc)
Add UTIL_ASSERT
Add test for assert
Add algorithm.hpp
Update cmake
Make algorithms inline
Import testing (not finished)
Add euclid_distance and relative_error
Introduce io::show
Importing finished
Merge branch 'testing' into cuda
Rename util/CUDA into cujak/cuda
Refine name space
Make cuda optional
Rewrite README