Moved CocoaPod and Xcode Subproject setup sections to dedicated documents.
Updated `Start Using Apptentive` section of readme.
Added Feedback button section in readme.
Added screenshot.
Fixes IOS-382
Moved surveys above Upgrade Messages
Modified readme to explain Survey interactions.
Added rating prompt images
Moved project setup docs to iOS repo from docs repo.
Added links to the project setup docs.
Moved FeedbackDemo section to top of readme.
Updated readme
Updated `FeedbackDemo` section
Updated readme
Moved new images to link to readme branch for testing; need to revert before release.
Resized images.
Resized survey screenshot.
Removed Metrics section (now covered by events).
Moved integration and testing guide to iOS repo
Added testing section to readme.
Updates to Testing doc
Added screenshot of rating flow event selection.