collection#upto doesn't include the maximum expression

[alexanderpann]

Example: 1.upto(9).sum equals 36 and not 45 because it sums up 1 up to 8. This is really counter-intuitive.

I propose a second argument inclusive that is set to false by default to not make a breaking change.
For example: 1.upto(9,inclusive=false).sum and 1.upto(9,inclusive=true).sum