fixed diagrams in several chapters - starting next section of chain rule -

Outlined presentation. Need to some how left justify it.
fixed bkgnd image and made the title environment better.
working, implicit diff coming along
Fixed typos
First two sections of chain rule drafted.
chain rule chapter is basically written modulo typos (that I am unaware of)

Started the trig section
fixed typo
More of the skeleton of the presentation
Merge branch 'development'
Merge branch 'development'
Draft of message for Week 5
Merge branch 'development'
New advertisement for the textbook
Merge branch 'master' of github.com:ASCTech/mooculus
Week 5 is now the current week
Removing requires from math-function
fixed very very minor typos
Merge branch 'master' of github.com:ASCTech/mooculus
Reduced powers to fix overflow issues - hopefully it works this time.
Merge branch 'master' into development