Priority GUI improvements

[fscan]

IProrityHost now allows the GUI to always show an icon to return to the original GUI

[orod-org]

SonarQube analysis reported 62 issues

• 17 critical
• 32 major
• 12 minor
• 1 info

Top 10 extra issues

Note: The following issues were found on lines that were not modified in the pull request. Because these issues can't be reported as line comments, they are summarized here:

1. GuiPriority.java#L182: Reduce the number of conditional operators (6) used in the expression (maximum allowed 3).
2. DualityFluidInterface.java#L355: The Cyclomatic Complexity of this method "usePlan" is 13 which is greater than 10 authorized.
3. DualityFluidInterface.java#L377: Refactor this code to not nest more than 3 if/for/while/switch/try statements.
4. DualityFluidInterface.java#L404: Refactor this code to not nest more than 3 if/for/while/switch/try statements.
5. DualityFluidInterface.java#L457: Refactor this code to not nest more than 3 if/for/while/switch/try statements.
6. DualityFluidInterface.java#L608: Add a nested comment explaining why this method is empty, throw an UnsupportedOperationException or complete the implementation.
7. PartFluidStorageBus.java#L285: The Cyclomatic Complexity of this method "getInternalHandler" is 15 which is greater than 10 authorized.
8. PartFluidStorageBus.java#L332: Refactor this code to not nest more than 3 if/for/while/switch/try statements.
9. DualityInterface.java#L623: Refactor this code to not nest more than 3 if/for/while/switch/try statements.
10. DualityInterface.java#L632: Refactor this code to not nest more than 3 if/for/while/switch/try statements.