[windows][mem]: change to use Performance Counter on SwapMemory.

[shirou]

Fixes: #1511

SwapMemory on windows was incorrect. This PR change SwapMemory to adjust psutil implementation. It is a method of calculating the actual value by using the Paging File(_Total)% Usage from the Performance Counter to determine the value.

Note: This PR will significantly change the value of SwapMemory on windows.

• psutil

  PS gopsutil\mem> python3 -c "import psutil; print(psutil.swap_memory())"
  sswap(total=15569256448, used=119250944, free=15450005504, percent=0.8, sin=0, sout=0)

• Before

  PS gopsutil\mem> go test -run TestSwapMemory -v
  === RUN   TestSwapMemory
  mem_test.go:81: {"total":32110739456,"used":17000914944,"free":15109824512,"usedPercent":52.944638560241316,"sin":0,"sout":0,"pgIn":0,"pgOut":0,"pgFault":0,"pgMajFault":0}

• After

  PS gopsutil\mem> go test -run TestSwapMemory -v
  === RUN   TestSwapMemory
  mem_test.go:81: {"total":15569256448,"used":119250944,"free":15450005504,"usedPercent":0.8,"sin":0,"sout":0,"pgIn":0,"pgOut":0,"pgFault":0,"pgMajFault":0}