[feature request] red text for negative resources

[Cainehill]

Plus, the little negative number tends to let me know that it won't be built this turn.

However - showing something in red to indicate that unrest is so high that you can't recruit anything would be handy, since unrest isn't displayed in the recruitment screen, and you can still have resources available. This would help people avoid wasting time and tying up gold because they didn't realize either that unrest was so high, or that you couldn't recruit when unrest was that high.

And a bug fix, to display the number of resources available when you _did_ recruit more than could be built in the previous turn. (Currently, going -40 in a province with 100 resources results in the next turn displaying 30 resources available, rather than 60.)