Rookie scales customizable

[luso97]

Pull request for issue #372. I created four new settings for the league:
-Rookie scales: Rookie scales for the draft. The contract are capped by the max and min contract.
-Rookie scale: Boolean for activating a rookie scale, independent of the hard cap
-Automatic Rookie Scale: It changes the rookie scale so that the maximum is not bigger than the max contract multiplied by the next setting
-Rookie scale Max contract ratio: Determines the maximum contract of the rookie scale as a ratio of the rookie scale.

The way I did it, if you go over the cap signing a rookie because of the scale, the league does not care. So if all 2nd rounders and beyond get 30M$ a year your team could get a salary of three times the salary cap, but obviously I think people would try to do a sensible rookie scale.

The only problem I found is that with these settings on in Football-GM, the players are signed automatically, which is probably odd for football. I was thinking about maybe making another setting to set the second and following rounds without rookie scale in Football-GM. Or just making the signing of the rookie optional, so that when you try to negotiate the salary of the rookie the only option is the rookie scale salary.

Edit: I changed this and now in the football game the rookies are always optional to sign, but if you sing them you have to sign them to their scale salary.

[dumbmatter]

I am so sorry I haven't reviewed this yet. Just stopping by to comment that, while working on some FBGM improvements, I noticed it uses the rookie scale when creating a new league, but then doesn't use it for any future draft classes. Well, not just FBGM, any new league with hardCap enabled. Which is bad cause it suppresses salaries significantly in a new league. Anyway, I'm going to fix that at least, but it's something to think about when I get to looking at this PR.