function padRight(string, length, chars) {
      string = string == null ? '' : String(string);
      return string ? (string + createPad(string, length, chars)) : string;
    }
Pads `string` on the right side if it is shorter then the given padding
length. The `chars` string may be truncated if the number of padding
characters exceeds the padding length.

@static
@memberOf _
@category String
@param {string} [string=''] The string to pad.
@param {number} [length=0] The padding length.
@param {string} [chars=' '] The string used as padding.
@returns {string} Returns the padded string.
@example

_.padRight('abc', 6);
// => 'abc   '

_.padRight('abc', 6, '_-');
// => 'abc_-_'

_.padRight('abc', 3);
// => 'abc'