Merge pull request #617 from jay-hodgson/SYNR-561

SYNR-561: link to the updated R API docs
register global window close handler to ask for confirmation when navigating away
SWC-957: warn on navigating away from Synapse, as well as if the place changes and we know that we are in edit mode in some Activity
from code review
Merge branch 'SWC-957' into release-17
Merge pull request #621 from jay-hodgson/release-17

Release 17