use MonoGame asm built from source (e86d8cfc15)
single-frame animations don't need a duration
don't scale the position in Sprite base

This doesn't make sense for all sprites. For example, it won't work for
the cursor sprite, which is always anchored to the mouse cursor's pixel
coordinate.
fix compile error after MonoGame asm update
allow a sprite's pixel position to be set
hide the mouse cursor while in the game
add a hand cursor
fix runtime error after MonoGame asm update
need to draw lines for the grid and cursor box
private constants are just another field
need to get coordinate for mouse cursor
draw the cursor box
yellow for grid lines too faint on the grass
draw the grid rows in the right place

Is an off by two error better than an off by one error?
draw the grid columns in the right place

They were actually already in the right place, but it was completely
accidental.
use the new primitive extension method
a temporary, naive pathfinder
set the player's path on mouse click
movement belongs in player, not sprite
move along the path