Script timeout thread to forcefully terminate the current thread of V8 execution in the corresponding isolate.

Note that threads are implemented using std::thread which is only available in C++0x. The relevant compile flags have been added but compiler support has not been tested and is therefore not guaranteed.
Added my name to the credits :-)
Implemented memory limit checking. Increased stability for V8 execution isolates.
Renamed V8JsException to V8JsScriptException and added V8JsTimeLimitException and V8JsMemoryLimitException classes.