make it easier to use in elixir ?

[dfang]

1. publish to hex.pm
2. add doc

[terry-xiaoyu]

This lib is still at the very early staged and cannot be used in production. We are plan to use it in emqx this year (after it is production ready), and I will also publish it to hex.pm.

[kjellwinblad]

I think this library can be considered production ready at this stage. At least with the default option to use the port program backend, the library should be safe to use as problems with the jq library should not cause crashes in the Erlang VM.

@dfang pull-requests that would make it easy to publish to hex.pm and to imporve the doc would be appricated.