Fix an issue with creating tasks directly into milestone columns

Summary:
These columns were conflating `projectPHID` (the defualt project to add to the task) with `boardPHID` (the board the column appears on).

Separate them to fix the beahvior.

Test Plan: Used "Add Task" from dropdown menu of a milestone column on a parent project's workboard.

Reviewers: chad

Reviewed By: chad

Differential Revision: https://secure.phabricator.com/D15242

webroot/rsrc/js/application/projects/WorkboardController.js

@@ -158,14 +158,14 @@ JX.install('WorkboardController', {
       var column_data = e.getNodeData('column-add-task');
       var column_phid = column_data.columnPHID;
 
-      var board_phid = column_data.projectPHID;
+      var board_phid = column_data.boardPHID;
       var board = this._getBoard(board_phid);
       var column = board.getColumn(column_phid);
 
       var request_data = {
         responseType: 'card',
         columnPHID: column.getPHID(),
-        projects: board.getPHID(),
+        projects: column_data.projectPHID,
         visiblePHIDs: column.getCardPHIDs(),
         order: board.getOrder()
       };