[BLUEJ-1213] bluej.utility.javafx.HangingFlowPane should be re-written

The class {{bluej.utility.javafx.HangingFlowPane}} is a copy of the JavaFX FlowPane class, renamed. It has numerous issues, including use of deprecated methods and a number of package private methods which aren't called directly and which don't override the superclass since it is in a different package. It is effectively a snapshot of what is now quite old JavaFX code.

The whole class should be re-written (probably from scratch) to avoid these issues.

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Issue metadata

• Issue type: Task
• Priority: Medium