Ensure UserInputPanel maximizes reuse of UserInputPanelAutomationHelper, ensure automatic installation can be generated from console for custom fields
Refactored so the GUICustomField and ConsoleCustomField utilizes the
same interface. This helps better represent the common functionalities
between the two types of fields.
Merge pull request #236 from mtjandra/IZPACK-1135

[IZPACK - 1135] - Ensure custom field generate automatic installation file through console installation