Oct 21, 2020; Update 134

Fix bug reporting PREDICT values for a covariate
Faster absorb step in some very large models
Fix conversion of var(loadings) from Gamma to Sigma scale (VPREDICT)
Allow at(Rep,0) as alternative to zero and zero(1) in the model
Warn if GRM nearly singular.
Bug getting Score for GDENSE Sparse stored GIV