Some more refactoring

src/main/java/sinalgo/gui/GraphPanel.java

src/main/java/sinalgo/gui/dialogs/GenerateNodesDialog.java

src/main/java/sinalgo/gui/dialogs/GlobalSettingsDialog.java

...main/java/sinalgo/gui/dialogs/GraphPreferencesDialog.java

src/main/java/sinalgo/gui/dialogs/HelpDialog.java

src/main/java/sinalgo/gui/dialogs/NodeInfoDialog.java

...in/java/sinalgo/gui/dialogs/PercentualProgressDialog.java

src/main/java/sinalgo/gui/helper/Arrow.java

src/main/java/sinalgo/gui/helper/MultiLineFlowLayout.java

src/main/java/sinalgo/gui/helper/NonRegularGridLayout.java

src/main/java/sinalgo/gui/helper/UnborderedJTextField.java

...n/java/sinalgo/gui/multiLineTooltip/MultiLineToolTip.java

src/main/java/sinalgo/gui/popups/AbstractPopupMenu.java

src/main/java/sinalgo/gui/popups/EdgePopupMenu.java

src/main/java/sinalgo/gui/popups/EventPopupMenu.java

src/main/java/sinalgo/gui/popups/NodePopupMenu.java

src/main/java/sinalgo/gui/popups/SpacePopupMenu.java

src/main/java/sinalgo/runtime/GUIRuntime.java