Added Sault College of Applied Arts & Technology

I wanted to restrict the eligible emails to students only (@student.saultcollege.ca) subdomain.

Sault College is based in Sault Ste Marie, Ontario and their website is available at http://saultcollege.ca/.

I am a student there and had to submit many requests to Github to get them to approve my application for the student plan. I figured I could help contribute to open source and maybe save some students and GitHub employees some time in the future.

Thanks!