R1:c01f23adfb82

Improve some column behaviors for Milestone/Subproject columns

Summary:
Ref T10010.

- Don't allow milestones to be reordered.
- Hide phantom subproject columns when reodrering.
- Don't allow subproject/milestone columns to be renamed.
- Force milestones to be ordered at the end, and in the correct order.
- Add some missing crumbs.

Test Plan: Reordered columns, renamed columns, made a new column, viewed column details.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10010

Differential…