Add support for human-readable queries

[almightycouch]

This is something I missed for really long time 😜.

Basically, it implements the Inspect protocol for RethinkDB.Q. It also transform references (within lambdas) to variable names (a, b, c, etc.).

Only downside is that we have an external JSON resource. The file has been taken from the official Java driver and shrinked down to contain only the the necessary ReQL id => name mappings.

import RethinkDB.{Query, Lambda}

table("people")
|> filter(lambda &(&1["age"] >= 21))
|> IO.inspect

Prints

filter(table("people"), fn(a, ge(bracket(var(a), "age"), 21)))

[hamiltop]

Awesome.