Minimal changes to get zero Dialyzer warnings
Nice to see that Dialyzer caught a bug from parallel development,
adding the is_empty_estimate/1 function, and today's merge of
the new QuickCheck model.
Remove type inference cruft
ran dialyzer on this branch and all looks good. Changes look good to me. I'm not super familiar with the erlang:random vs. erlang:nif_error usage in the nif placeholder funs so perhaps there is something subtle there i am not aware of.
tl;dr +1 but perhaps a second quick review would be good since I'm still getting familiar w/ the bitcask source.