Fixed Token Blurriness, Added "Visibility" Toggle — Digital TableTops VTT Steam update #1569769

It's been the #1 bug report for a while, but token blurriness is no more! I was going about it the wrong way and put off fixing the code. But it is done, and tokens should be getting rendered at up to 256 ppi! Better yet, there shouldn't be any performance penalty! It might slightly improve performance even though all tokens are being rendered twice. Most displays are much lower than 256 ppi (mine is a measly 56) and if you do happen to have a super high resolution display, at least the tokens will be about 4 times crisper than before. Hopefully that is enough :) This change made it trivial to add another feature: a "Visibility" toggle for individual tokens. To access it, simply right-click on any token from within the DM screen. Toggling it on/off makes the token visible/invisible on the player screen. It will only appear for NPC tokens. I could not think of a compelling reason why play...