HUBOT_MARKOV_RESPOND_CHANCE env var cannot contain '.'

[bnfinet]

we've set the env var HUBOT_MARKOV_RESPOND_CHANCE to 0.005 for very infrequent but very humorous responses.

Unfortunately this line...
https://github.com/smashwilson/hubot-markov/blob/master/src/config.coffee#L6
tests for digits and fails on '.'

can I suggest
/^[-+]?[0-9]*\.?[0-9]+$/.test

Thanks for helping us to brighten our days with markov enabled hubot!

[baudehlo]

I fixed it by setting it like this:

    respondChance: parseFloat(hash.HUBOT_MARKOV_RESPOND_CHANCE)

[baudehlo]

The fix also requires in default-listeners.coffee changing preprocessor.words( to processors.words.pre(

[scarolan]

@bnfinet have you sent a pull request for this? Your fix worked for me.

[Bajotumn]

Fixed in #29