[Volunteer Mobilization] Build tagging UI for documents

[pmn]

The system will need a UI for users to apply tags to portions of documents. Should free-form tagging be allowed, or should tags be considered a voting signal?

For example, free-form tagging would allow users to mark documents with things like: [interesting] [important] [critical], etc; creating a "Tag as commentary" environment.

On the other hand, pre-defined tags would present a series of tags for an entire document set, in which selection of a tag would be construed as a vote for that category on that tag. So clicking on the [important] tag would be seen as a vote for the portion of the document being "important" (tags defined by the questionnaire creator from issue #2)

[pmn]

As a suggestion, a scoring mechanism may be an interesting way to encourage volunteers. Points given for being the first to discover an interesting fact, for voting with the crowd on a fact that gets confirmed by the questionnaire creator, bonus points granted for a variety of reasons, etc. Not that internet points ever motivated anyone to do anything....