Added documentation for the "title" attribute

Added documentation for the "title" attribute
refined documentation related to title attribute
pointing to new REST API docs
Merge branch 'SenderFix'
Minor spelling corrections/suggestions.
Adding initial guide for the KC Admin, shipped with the UPS
small typos
Applying abstractj review comment
Little note about SSL and Keycloak
Merge branch 'KC_Admin_Console'
update tutorial to latest
update based on matzew feedback
reduce img sizes to avoid redundant download
shrink the size of iOS devices screenshots
added sentences for setting custom payload using the rest-sender api with curl
Merge branch 'pr/353'
update notif msg. to be consistent with the ups-guide
Link to REST API and Node.js Sender example
fix language issues (fail back / to be send)

Conflicts:
	docs/unifiedpush/aerogear-push-ios/unified-push-server.asciidoc
update SimplePush guide