support hide window in windows

[yunxuanhao]

During my software development, I am required to compile CGO programs for various platforms. On Windows, it is necessary to include a specific flag -H=windowsgui to hide the console window, which is not suitable for other platforms. I wish to integrate the hidewindow parameter into the xgo command such that it automatically appends the -H=windowsgui flag when the target platform is Windows.

#128