Increased timer precision

When waiting for a frame deadline, just sleeping until the objective is varyingly imprecise. A better solution is to modify the [timer resolution](https://docs.microsoft.com/en-us/windows/win32/api/timeapi/nf-timeapi-timebeginperiod), sleep until some small unit of time *before* the deadline, and then spin wait for the remaining time segment. This will significantly reduce frame time variations.