Closes #1428 (closed) I remembered we had this issue somewhere in Cylc, and fixed it after working with existing code. This MR simply copies the code responsible for sorting keys in Cylc workflows on terminal TUI (which can be quite large). Will check performance, and will see if there's a test there that we can copy too (although it has doctests, which could be enough to fully cover the test -- we just need to make sure pytest is running doctests).