* Converted all instances of "256" spotted to use RegionSize instead. Some approximations used for border crossings (ie 255.9f) are still using that value, but should be updated to use something based on RegionSize.
* Moving Terrain to a RegionModule, implemented ITerrainChannel and TerrainModule - nonfunctional, but will be soon.
* Cleaned up copyright notices in AssemblyInfo.cs's
* Added Copyright headers to a bunch of files missing them
* Replaced several common string instances with a static constant to prevent reallocation of the same strings thousands of times. "" -> String.Empty is the first such candidate.
