Some expansion of help
Added and changed levels of requirements around metadata
Moved release type question out to general section
Changes to privacy-related questions etc

includes adding disclaimers to questionnaire and certificate
Tweaks to wording around data listing questions
added help (legal section help now complete)
completed help for 'practical' section of questionnaire
updated help in Technical section
changes to ownership section, following chats with @davetaz
merged changes from master