Cast the METHOD_FINDER_DEBUG environment variable to a boolean (#17)
Cast the METHOD_FINDER_DEBUG environment variable to a boolean (#17)

* Cast the METHOD_FINDER_DEBUG environment variable to a boolean:

e.g.:

    $ METHOD_FINDER_DEBUG=1     irb # true
    $ METHOD_FINDER_DEBUG=true  irb # true
    $ METHOD_FINDER_DEBUG=0     irb # false
    $ METHOD_FINDER_DEBUG=false irb # false
    $ METHOD_FINDER_DEBUG=False irb # false
    $ METHOD_FINDER_DEBUG=FALSE irb # false
    $ METHOD_FINDER_DEBUG=      irb # false

This is a lightweight alternative to the solutions proposed here:
https://gist.github.com/equivalent/3825916

Uses String#match instead of String#match? for compatibility with 
Ruby < 2.4.0 i.e. JRuby 9.0, which implements MRI 2.2

citizen428/methodfinder,citizen428/methodfinder