metomi/rose#723: fix section add bugs
metomi/rose#723: fix section hint in add dialog
metomi/rose#723: update
Fix a typo.
Merge pull request #734 from arjclark/command-key-typo

tutorials: command-keys: Fix a typo.
metomi/rose#723: alter error report to dialog
Merge pull request #727 from benfitzpatrick/723.rose-edit-add-blank-section-bug

#723: fix rose edit section add bugs
Merge branch 'master' of github.com:metomi/rose into gh-pages