SERVER-14802 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
It would be better to go with the following change below so that it follows our header include rules. I have verified this on my local Windows machine. The basic.h file ultimately includes Windows.h, and sets all the right defines.

```
+#include "mongo/platform/basic.h"
+
 #ifdef _WIN32
+#include <mmsystem.h>
 #include <crtdbg.h>
 #include <stdlib.h>
 #include <stdio.h>
 #endif

 #include "mongo/base/init.h"
 #include "mongo/util/log.h"
 #include "mongo/util/stacktrace.h"
```