Workboards - add column detail page

Summary: followup to D8544. This ends up creating an editor + transactions to get the job done.

Test Plan: made a column - saw a nice created transaction. edited the name - saw a nice name edit. deleted the column - saw a deleted transaction, updated "deleted" ui, and hte action change to activate. "Activated" the column and saw a transaction and updated UI. Tried to delete a column with tasks in it and got an error.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D8620