Qutip 4.5.2

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)