Rename email action in example
Fix fallback URLs
Version bump to 0.5.2
Fix defaultVC behavior of apps using fallbacks

Shows the fallback app's name again, but disallows selection.
Default app can be one that wasn't specified

Previously, not having the default app for a given handler installed
resulted in the default being the fallback, even if another app was
available. This causes the default app to fall back to the first
available app if not the default.

(For now, this is really only relevant to Twitter, the only handler both
with no first-party default and with multiple handlers)
Add example image for INKDefaultsViewController
Update CHANGELOG
Perform URL encoding more lazily

This sets the stage for loading view controllers in INKActivity objects,
where we won't want parameters to be escaped.
Can send email using modal view controller
Create INKPresentable protocol
Make INKActivity aware of its presenting view controller

Necessary to present modal view controllers in the correct context
Backfill tests for view controller / mail sheet behavior
Add CocoaDocs for INKMailSheet and associated code
Fix mocking issues causing test failures
Don't escape commas in URLs
Add in-app modal UIWebView as a web handler
Make in-app handlers the default for mail/browsers
Add toolbar to in-app web browser
Don't show first-party apps if an equivalent in-app version exists

e.g. Safari vs UIWebView, Mail.app vs MFMailComposeViewController
UIWebView share sheet shows in a popover on iPad