Added Mac fing finding ip instructions handy guide and correct mac/linux ssh instructions

I have done the mac section of the finding your ip handy guide. I also filled the iOS section with a placeholder to tell people I'll do it soon so no one else starts (it would be a waste). I will do it soon (today, tomorrow or next few days).

I also corrected the ssh connection Linux/Mac as you cannot use Ctrl+Alt+T, you have to open it, so I said use the shortcut on linux, and explained how to open it on mac).