JOC should remember the width of the tree panel

Current Situation
If a user modified the width of the tree panel - in any view including the Configuration view - then the width is reset if the user switches views and return the to view for which the tree panel was modified.

Desired Behavior
The width of a tree panel should be the same per view throughout a JOC Cockpit session, i.e. when switching views and returning to a view for which the tree panel width was modified, then the modified width should be active.