Switching ./bin/fibrous -c to use CoffeeScript's REPL

This solves two problems:
    (1) It lets you enter multi-line input into the REPL, which
        is often quite convenient in CoffeeScript
    (2) It stores history to a file, so input history is preserved between
        sessions (i.e. you can hit the up arrow immediately upon starting
        the REPL and it will work)

Everything else still works the same

Tested by using REPL, ex.:

    ccheever@Charlies-MacBook-Air:~/projects/fibrous$./bin/fibrous -c
    Starting fibrous coffee REPL...
    coffee> fs = require 'fs'; null
    null
    coffee> readme = (fs.sync.readFile 'README.md').toString(); readme.slice
    'Fibrous\n=======\n\nEasily m'
    ------> ml = (x) ->
    .......   x + x
    [Function]
    coffee> ml 3
    6
    coffee>

And the regular Node version still works

    ccheever@Charlies-MacBook-Air:~/projects/fibrous$./bin/fibrous
    Starting fibrous node REPL...
    > function f(x) { return x * 2; }
    undefined
    > f(3)
    6
    >