* Optimized the drawing of lines and tracked entities
* Optimized nav map updating and added thin wall support
* Added support for thin doors
* Removed floor tile seams, more line drawing optimizations
* Fixed split grids not updating correctly
* Cleaned up NavMapControl code
* Fix nav map header
* Converted nav map updates from system network messages to delta-states
* Addressed review comments
* Fixed timing issue where NavMapSystem would update before AirtightSystem did