Bug Fixes

zcsr_proj does not fail with unsorted indices (by Jake Lishman)
Fixed Milstein's heterodyne errors (by Eric Giguère)
Removed risky code (by Jake Lishman)
Fix datatype bug in lattice (by Boxi Li)
eigh issues on mac with openBLAS fixed (by Eric Giguère)
Improvements
Faster zcsr_inner (by Jake Lishman)
Support for Scipy 1.5 (by Jake Lishman)
Better error message when installing without numpy (by Eric Giguère)
Book keeping
Various code style improvements (by Jake Lishman)