progress on storage rollingstock #TrainsInMotion #Traincraft (1.7.10 rewrite)

- Removed some useless functionality from the bogie and train core.
- Improved the movement and brake handling for trains and rollingstock.
- Bogie positioning is not defined by doubles, there was no reason for it to be floats before.
- Added the entity, item and model for the VAT Log Car.
- Expanded the transport types and added some documentation.
- Added filtering for Log Cars.
- Seats are now removed on entity destruction.
- Added some rendering, inventory percentage calculation, and a custom image to cover the custom logs, this is still very unfinished.
- Added a transparent texture, and removed the useless hitbox texture.
- TMT CHANGE: added a new function for adding a box with a pre-defined name, this will make adding animation support to models significantly easier.


This covers a huge portion of the code that's left to finish for before the first alpha release of TiM.
Just need to handle the GUI stuff, and finish the dynamic textures.