If our win32 monotonic timers are not monotonic, make them so.
There's a rumor that sometimes GetTickCount64 or GetTickCount can move backwards. This is possibly due to a misunderstanding of bug #23558 (moved) (fixed with 77cc97cf0a20ed0a062a1cb87bef6c40941e4cff
). But in case it isn't, we should fix it.
(QueryPerformanceCounter can move backwards, and we have code to handle that.)
Putting this ticket in tor:unspecified since I don't actually think we have a bug here.