re-adding the teaching folder

- Added the teaching folder... (needed for http://wurmlab.github.io//teaching) 
- Compress teaching/2014msc/AntWebFieldGuide.pdf (from 80mb to 8mb)... (this compression was necessary - this massive file was making it hard to push, even after increasing the buffer size). The file is now at 'medium' quality and so is still printable.