Started building out an auction channel
Added a thief class (just to test multiple classes).
Moved skills around a bit, and brought the default isOnCooldown and setCooldown methods for skills into player.js
This way you don't need to explicitly set them each time.
They can be over-ridden with onCooldown and offCooldown handlers on the skill.
Doesn't throw with other implementations where all cooldown handling is in the 'activate' method (tackle still works).
But probably is setting and removing the cooldowns twice.