Replaced the link to obsolete Pyfft with the link to Reikna.
Merge pull request #36 from Manticore/pyfft-to-reikna

Replaced the link to obsolete Pyfft with the link to Reikna.
PEP8 test_gpuarray
Make GPUArray.view() respect strides (fixes #38) (reported by Hannes Bretschneider)