Merge pull request #20 from limenet/master

Fixed typos in chapter 6, 7
Automatically generated PDFs
Continued work on chapter 3
Generated New PDFs
Chapter 2 reviewed

Several errors in math and transcription and spelling errors
Merging
Finished PDF week 5 (Chap 3)
Generated New PDFs
updated readme
Continued work on chapter 3, other

- Continued work on chapter 3
- Added C as set for custom command
removed leftover file
Generated New PDFs