Beta Release Near!

A majority of the improvements in this release involved the collision system, and the animation API.

Now, the collision system is integrated into the polygon primitives, rather than within the entity. This makes different routines easily possible through inheritance, rather than zen::obj::zEntity attempting to cover all generic cases. There are still many kinks to work out and bugs to fix, and documentation to update, of course.

The animation API is still fairly fresh, and has basic functionality that has been essentially hacked together, but will be perfected throughout this major version.

I won't be updating the major revision number as changes to the animation API are made, simply because I am considering it to be in a very developmental stage, and expect there to be a lot of breaking changes.

I also hope to have 5.0.0-alpha be the final major alpha release, with the next stage progressing to 1.0.0-beta. I am beginning to develop a game using the engine internally, which means its nearing production quality.