Fixed as_numer_denom for Adds
Minor changes to printing tests
Mino changes to tests
Minor change to assoc_legendre
Minor change to pretty test
Minor test change
Simple test change
Temporary stuff
Changes to _dist_const
Fixed refine
Fixed match
Fixed factorial/gamma rewrites
Minor test change
Fixed primitive
Matrix fixes
Changes to _keep_coeff

We still need this, because it handles conditional distribution cases.
Re-fixed could_extract_minus_sign
Fixed deltaproduct
Changes to factor_terms

We get to remove some special handling here
Minor test change