Committing several fixes for LES on CPU and GPU.
Dynamic LES now does the same thing on CPU and GPU. Whether this is the 'right thing' remains to be seen.
Fixed a bug in strain calculation which affected the magnitude of the eddy viscosity calculated by Smagorinsky and WALE models.
Merge branch 'feature_LES' of https://github.com/fpalacios/HiFiLES into feature_LES
typo in modal filter.