Integer overflow problem in string::compare()

[Dan Kegel]

Hi Piotr,
could you review the patch in http://bugs.winehq.org/show_bug.cgi?id=31085 ?
If you like it, I'll submit it to wine-patches.  It passes winetestbot and
gets pulsen and stepmania past the splash screen abort.

Why are there no tests for msvcp60?
If you think it's appropriate, I can add the fix and test for msvcp60 as well.

Thanks for all your hard work!
- Dan