GUI - Element properties - add interface to delete properties

[shawnlaffan]

Sometimes a user will attach group or label properties which are not needed. It would be useful to add an option to remove these.

The usual condition would apply that the basedata should not have any existing analysis outputs, as the properties might have been used in them.

To do:

• Remove all properties
• Remove a subset of properties (allows users to import large list and then subset).
• Error message for basedata with analysis outputs could suggest the user clone without outputs
• Frames/panes should expand vertically as window is enlarged (i.e. lower edge is dragged down)
• [interface changed] Interface could be more tabular, similar to the view labels list. Then we can pack everything into one table, indexed by element on the left. Checkboxes can be used to delete all props for an element, or props across all elements. Individual deletions can be done using a multiple cell selection process.
• [skip this one] Need to check if basedata is updated when its view labels tab is open. That is perhaps a larger issue, though, as none of the processes handle that at the moment (e.g. the label lists are not updated if label props are imported while the view labels tab is open).
• Dialogue needs a close button
• Natural sort order for lists
• Delete all properties for selected elements, delete property from all elements
• Project set dirty
• Undo last selection (need to stage the deletions)
• add an apply button
• rename other buttons to "schedule for deletion"

[shawnlaffan]

Mark as fixed.