* 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.
Changed "ObjectID" in ScriptEngine to IScriptHost reference. Events will now be queued based on IScriptHost reference instead of string ID of object. Removed "root" object reference in script.
* Changed how Script accesses World
* Implemented llSay, llWhisper and llShout
* Added SetText() to IScriptHost, implemented llText
* Minor renamings to conform with code conventions