Adding a new example that displays all the tween behaviors.  This is just a dummy melonJS app.
calculate how many tweens exist and adjust the height of the canvas to fit an example of each tween.
-Rename entity and correctly add to entity pool
-clarify calculation for canvas height
-remove unneeded code for loading a level (don't use one).
-create a new robot entity at evenly spaced y positions for each tween
type.  When robot is created automatically create and start a tween.
-print the name of each tween to the screen.
-Each robot has its own tween and it simply tweens between both edges
of the screen.
-Add a link to the tween doc to the web page.
-Remove unused variables
-Added a margin to the left and right sides so the elastic tweens can
be seen easier.
-change background color
-removed unused resource.
-code cleanup
-after a tween finished start it over at the left side of the screen.