example:

  console.log DIFF.analyze "this is some test. blah blah blah", "this is other text. blah blah blah"

  [ [ 0, "this is " ]
    [ -1, "some" ]
    [ 1, "other" ]
    [ 0, " te" ]
    [ -1, "s" ]
    [ 1, "x" ]
    [ 0, "t. blah blah blah" ] ]

  console.log DIFF.colorize "this is some test. blah blah blah", "this is other text. blah blah blah"