fixed wiki link issue.
Implemented delete from the UI side.
converted over to ReThinkDB for users, designed page models for easy access to all desired features for the wiki.
Added required functionality to the pages section.
converted to using the new rethinkdb calls.

This is a huge conversion from the previous design, and there are still some outstanding issues, which will be fixed in later commits.
fixed tags.
initial page history support.
Added support for viewing a page at a given revision.
finished recent activity, tweaked history, cleaned up some other things.
Updated readme, package.conf
Merge pull request #1 from Morgul/ccase-rethinkdb-backend

ReThinkDB backend