Workboards - fix adding new tasks and sorting

Summary: At least on my install, sorting was pretty borked from a type issue. (e.g. "unbreak now" of 100 sorting as less than "High" of 90). Fix this with some parseInt action. Also support adding new cards with the new colsort stuff. The clever bit here is to include the task ID in the sorting vector because the task ID wins ties at the moment I think / new tasks need to show up before older tasks when they are initially created. Fixes T5716.

Test Plan: added many "normal" priority cards and saw them fly in correctly. changed priority and moved correctly. made no edits and no moves were made correctly.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T5716

Differential Revision: https://secure.phabricator.com/D10081