parse scenario number ranges on CLI

Used a dash (-) to define a number range. Useful
when you have a certain amount of scenarios you want
to run, but don't want to type all the numbers using commas.

Number range is inclusive, so 2-5 becomes 2,3,4,5. ranges
can also be mixed with commas. e.g. 1,3-5,7 becomes 1,3,4,5,7.