Began intro to the Needs section
Update Reference Designs

clarity and comments on things Sam needs to do
Update Reference Designs 2 

spelled checked section 
Finished intro to Needs section, corrected typo
Merge judyedits: incorporates Judy's changes
Merged in Sam's edits based on Judy's comments
Merge branch 'needsintro': Added introduction to Needs section.
Merge branch 'master' of https://github.com/reinotsason/praxis