var ReverseMd5 = require('reverse-md5')
var rev = ReverseMd5({
    lettersUpper: false,
    lettersLower: true,
    numbers: true,
    special: false,
    whitespace: true,
    maxLen: 12
})
 
rev('49f68a5c8493ec2c0bf489821c21fc3b') //returns something like: {str:'hi', elapsed: 0.309135532}