added onActivateEvent callbacks to adding/removal of objects
[#543] added a proper collision filtering support
[#543] fixed the missing me.collision.types enumeration from the documentation

Kind of, as this is not working as expected with jsdoc3, so unless
somebody knows how to do, that's the best i could do here :(
[#394] documentation update

added an example for the new `me.collision.check`, and remove the ones
for the deprecated functions.
[#543] moved out the collision bitmask test into a `me.collision.shouldCollide()` function

this also somehow more follows the box2d philosophy and offers a
function that can be easily redefined if required
added the alex4 image showcase into the readme file
[#543] renamed `me.body.type` to `me.body.collisionType` to avoid any confusion with the previous implementation
[#543] added the full collision type list
[#543] use the correct bitfield when checking for collision with the collision layer
[#364] documentation fix
[#144] documentation fix
changed to use _patched over parent
add missing images
update styles for new template
Merge branch 'master' of github.com:melonjs/melonJS into new-jsdoc-template