Overhaul of Chapter 4 and fixing more *x* and the like in CMA05-5 & 6

Overhaul:

check *x* *y* *n* *r* and the like
Check -full on MathJax
Add Appendix to Nav
new norm in navigation
trade ' in nav &#8217;
look at ref in exercises
Add text roman to all lists
Check refs in chapter 2
Save as you go