[jed4] Add review restrictions

[JazParkyn]

Reviews can be left for any distribution type (free, paid, cloud service) providing that the type in question is listed.

User Restrictions:

• User must be logged in to submit a review
• A user can only have one published review for a distribution type of an extension
• When submitting a review, a user must first select which distribution type for which their review is for.
• A review can be submitted in any language, selected from a dropdown. If the person has already chosen to show the JED in a certain language, that language will be preselected for the review.
• Users will be able to submit new reviews which will automatically replace existing reviews, if the original is older than 6 months, regardless of published state.
• They will also be able to unpublish their reviews if they wish.
• The support score / comments is only shown if the developer has stated that support is available, and if the user has selected that they have used support.
• Scores to be entered on a 5 star scale, with half stars. There should also be an option to mark as ‘Not Applicable’ to give a NULL score (exempt from score calculations)

Review Publishing:

• All reviews are unpublished by default.
• All reviews are run through the Review Detector.
• If the result is negative, the review remains unpublished.
• If the result is positive, the review will be published, subject to the Reviewer’s permissions.
• Email notifications of a new review should not be sent unless the review is published.