Checkpoint: simple tests working again

No tests though
one-of working now
Simple random seed threading
Add such-that
Better document rng threading
Better naming and hacky shrink-seq hack
Add size varying support, cleanup vector shrinking
Test that tests are deterministic

Except for the random seed

Also remove the clojure_test_test tests for now, I can't see why they're
failing because of technomancy/leiningen#1201
Update README
Add count and concat test
Remove unnecessary `do`
Add interpose test
Fix interpose test
Add sorting test
Run 1k tests not 100
Merge branch 'use-value-polymporphism'