Number randomizer

Here's a [demo](http://codepen.io/ultimatedelman/pen/GKdfl). Add `data-draft-number` with the following format to add a random number:

 - optional. if first char is '$', dollar sign will be appended
 - required. include either a range of total digits or a single digit length: "2-3" will return a number of either 2 or 3 digits in length. "4" will return a 4-digit number.
 - optional. include the number of decimal places to include. single number: "2-3/4" will return a 2 or 3 digit number with 4 decimal places

for example: `data-draft-number="$/3-4/2"` would return a number like `$325.63` or `$6423.62`