Remove abbreviations from API's to make code more readable

[jeffreyyoung]

I think in most cases kaboomjs would be more readable for people new to programming if the API's did not use abbreviations.

For example:
pos(120,80) vs position(120,80)
anchor("botLeft") vs anchor("bottomLeft") - "botLeft" was confusing to me given that "bot" is a common word
rand(0,10) vs random(0,10)
rect(5,5) vs rectangle(5,5)

Besides that I've been loving kaboom!! It's been super fun to use!