v0.2 2019-01-14 Paris (France)

• Add pretty-printer
• Randomize pop action on the fuzzer
• Add tests on Rke and Rke.Weighted (with alcotest)
• Fix bug retrieved by ocaml-git (see 453633b)
• Add rev_iter function
• Fix bug on Rke.N.keep_exn (see 3951501)
• Add Travis CI support