GitLab

* setting imaginary parts of DCT and nyquist frequency to zero in IRSHT variants

* adding caching

* replacing many numpy calls with torch calls

* bumping up version number to 0.7.6

adding local SNO architecture and updating trraining script for SWE prediction with powerspectrum computation

Major Cleanup of SFNO. Retiring non-linear architecture and fixing initialization. Adding scripts for training and validation.