* Timing: Optimize Timestamp Aquisition
Currently, we make use of Environment.TickCount in a number of places. This has some downsides, mainly being that the TickCount is a signed 32-bit integer, and has an effective limit of ~25 days before overflowing and wrapping around. Due to the signed-ness of the value, this also caused issues with negative numbers. This resolves these issues by using a 64-bit tick count obtained from Performance Counters (via the Stopwatch class). This has a beneficial side effect of being significantly more accurate than the TickCount.
* Timing: Rename ElapsedTicks to ElapsedMilliseconds and expose TicksPerX
* Timing: Some style changes
* Timing: Align static variable initialization
* Started to rewrite the thread scheduler
* Add a single core-like scheduling mode, enabled by default
* Clear exclusive monitor on context switch
* Add SetThreadActivity, misc fixes
* Implement WaitForAddress and SignalToAddress svcs, misc fixes
* Misc fixes (on SetActivity and Arbiter), other tweaks
* Rebased
* Add missing null check
* Rename multicore key on config, fix UpdatePriorityInheritance
* Make scheduling data MLQs private
* nit: Ordering
