SERVER-9580 Fixed problem with sleepmillis() on Windows due to default timer resolution being typically higher than 15ms

All sleepmillis() calls with values lesser than timer resolution will sleep AT LEAST the timer resolution value, making Mongo be really slow on certain use cases. Like when implementing consumer/producer patterns using capped collections to stream objects back and forth
@benety , yes, we could do that. According to the documentation Windows will take the lowest value passed as a parameter so I assume there should be no issues with other threads calling this API with higher values breaking our logic in that way.