rngWithExcludedRanges(minimum, maximum, ranges)
ranges: is optional. Example [{minimum:2, maximum: 5}]
minimum: The lowest possible value in the range.
maximum: The highest possible value in the range. Inclusive.
Returns a Promise that resolves to a random number within the specified range.
Note that the range is inclusive, and both numbers must be integer values.
Error Messages
Any errors that occur during the random number generation process will be of this type.
The error object will also have a code property, set to the string "RandomGenerationError".