Add support for paths containing any mixture of single quotes and spaces

I was trying to install this on a friend's computer yesterday, and had trouble because her surname is "O'Doherty", which is also in the path to her AppData folder. After 10 minutes I gave up and moved the exe to a path without any apostrophes, but it annoyed me that I couldn't write the .gifconfig correctly to use paths with apostrophes, nevermind the bash command to correctly update the config!

After another few hours of playing, I've finally solved it, so, I hope this is useful! It's my first contribution to an open source project.

Thanks for all your contributions and for starting the project,

Sam