update 2.0 covers
learn to spel
trim images
Fix rendering and kickoff app guide
Move note
Drop intro. Bring application chapter up to date with changes to original repository.
Per Nathan, RAMP handily trumps HAT
Migrate conditional requests to chapter 3, since those are not conceptual, and remove anything not fully-baked from chapter 5
Merge pull request #39 from coderoshi/jrd-app-guide

App guide: better integration, drop much incomplete content
chap 1,2 updates
update developers
Added search
Add security section
merge
merge rebuild
merge