Add XML Utils for loading/saving files

...l/assets/de/tobias/playpad/assets/view/main/mainMenu.fxml

PlayWall/src/de/tobias/playpad/PlayPadImpl.java

...as/playpad/viewcontroller/main/MainMenuBarController.java

...obias/playpad/viewcontroller/main/MainViewController.java

...aypad/viewcontroller/option/GeneralTabViewController.java

...playpad/viewcontroller/option/SettingsViewController.java

.../viewcontroller/option/pad/PadSettingsViewController.java

PlayWallCore/src/de/tobias/playpad/PlayPad.java

PlayWallCore/src/de/tobias/playpad/plugin/PadListener.java

PlayWallCore/src/de/tobias/playpad/project/Project.java

...lCore/src/de/tobias/playpad/project/ProjectReference.java

...e/src/de/tobias/playpad/project/ProjectReferenceList.java

...de/tobias/playpad/project/ProjectReferenceSerializer.java

...Core/src/de/tobias/playpad/settings/ProfileReference.java

.../src/de/tobias/playpad/settings/ProfileReferenceList.java

...e/tobias/playpad/settings/ProfileReferenceSerializer.java

...obias/playpad/viewcontroller/ISettingsViewController.java

...ias/playpad/viewcontroller/SettingsTabViewController.java

PlayWallCore/src/de/tobias/playpad/xml/XMLDeserializer.java

PlayWallCore/src/de/tobias/playpad/xml/XMLHandler.java