Patch 0.31: Finalizing demo

Patch 0.31: - Max gold that gives interest from 600 to 500 (from max 60 to max 50 extra gold each round now). - Some upgrades that can only be upgraded a limited amount now show their progress and max upgrades possible, for example the Frost Shock duration upgrade will show “SPELL UPGRADE 0/5”. - When choosing new units their special abilities are now updated correctly if you have upgraded them. - Fixed various incorrect movespeed tooltips. I hope to have this be the final demo version, The demo updates have been small and slow because I am working on the full version (Tier 4 and Tier 5 units are done now).