[Issue] Reference documentation

As discussed on Discord with Soru, I use the forum to summarize little things I found.

• The buttons values are exposed as globals and documented as the way to use them.

This is not a very nice way to code (and this is not the case in CircuitPython mode)
Better, the values already exists as 

Button::down

Button::up

Can't we document the reference usage as the Button:XXX ?

• The collide methods in the documentation are the old version way to do stuff

gb.collideRectRect

gb.collidePointRect

...

The current way seems to be:

gb.collide.rectRect

gb.collide.PointRect

...