Make px, py actual player positions

Instead of the position of the top-left corner. This should make it
easier for zone scripts to identify location of the player relative
to in-zone.
Add name to 'entered the game' announcement.
Making the purpose of lpx and rpx clear, with comments
Remove vpx and vpy, they were never used.
Comment to define vpoffsetx and vpoffsety
Oops, a few variables in drawPlayer weren't local. Now they are.
Merge pull request #66 from captdeaf/master

Make px, py actual player positions