Timed movement and blinking

Made walk rate independent of framerate, which resulted in slower
movement on less powerful systems and overly fast movement on faster
ones.

Added blinking, when the character is idle for 2 seconds.
Collision handling

Added collision handling, although it needs work. Player does not walk
through buildings, AI is not started. TODO: fix "phasing" into buildings
(must stop player BEFORE they enter trigger BoxCollider2D).
Added Camera

Camera Motion Added, now tracks player.