demo 2 file

Changes:
-Changed from a 32x32 grid to a 48x48. This allows you to make a strategy without having to place a huge number of houses and towers, reduces clutter on the screen and improves game performance.
-Added a simple explanation paragraph in game
-Eliminated in frame HUD and moved it into the webpage
-Added a grid when in build mode to make the placements clearer
-various small glitch fixed and performance tweaks