Improving ipet gui

[JanMerlinV]

Some bugs and missing convenience features I noticed while using ipet to evaluate scip test runs, primarily relating to the gui. Note that the gui used was not the one from the ipet-gui script, but the ipet-evaluate script with argument -A.

First, a checklist and overview of the points. A more detailed explanation to every point follows below.

Bugs and missing convenience features in ipet gui

• Filter groups filtertype 'union' not working
• Default columns not readable
• Order of columns and filter groups fixed
• Adding children pops up all subtrees

-- Filter groups filtertype 'union' not working --
Setting a filter group's filtertype to 'union' from 'intersection' does nothing. It still generates the intersection of its filters.

-- Default columns not readable --
Adding a new column and saving it to the evaluation file without changing anything will lead to the evaluation file being unusable, only to be fixed by opening the .xml in an editor and deleting the column. This might be intended, but can be a trap nonetheless.

-- Order of columns and filter groups fixed --
Being able to change the order of columns and filter groups would be a nice convenience feature. Nothing fancy like drag and drop is needed, just an up and a down arrow would already be amazing.

-- Adding children pops up all subtrees --
Adding a child to anything will pop up every hidden subtree instead of just the selected one.

@GregorCH
@fschloesser