Tool supports loading multiple logs in one run

Tool does not crash anymore if you try to load multiple logs without closing the tool. Widgets are closed and opened as needed.

This solution requires the following to  be true about the use of ToolDiagram::addUnloggers, or there is potential for bugs:

// addUnloggers should only be called once for log folder
// IMPORTANT whenever this is called, all old unloggers and guis are deleted
// MUST follow the once per log folder rule for tool to behave correctly