Impl. IsMinimized

[SamLebarbare]

Expose win32 IsIconic:
https://docs.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-isiconic

This is usefull for showing windows and keeping the correct last state, ex:

const {Window, WindowStates} = require('win-control');
const win = Window.getByPid(pid);
if (win.isMinimized()) {
  win.setShowStatus(WindowStates.RESTORE);
} else {
  win.setShowStatus(WindowStates.SHOW);
}