Specify ttf file to extract from

[Mox4572]

I don't know exactly how this works but if you would add a way to specify a ttf file when running the command, it would be nice! The main use for this is for if you were to acquire an older version of the Apple Color Emoji font and to move it to a different computer though to use this script, perhaps one that you don't want to mess with the system folder on.