Make Dialog easier to extend

[F43nd1r]

I liked the default dialog, but I wanted to apply minimal changes to it. That is currently very hard. In my implementation (note: no logic changed) I have several Methods which can be overridden to modify just parts of the dialog:

• addViewToDialog can be used to add view to the start (call before buildCutomView) or end of the dialog (call after buildCustomView)
• getMainView, getCommentPrompt and getEmailPrompt allow to modify or replace specific parts of the dialog
• buildAndShowDialog can be used to e.g. prevent the creation of the dialog in certain situations
• getDialog for more modifications to the dialog (e.g third button)

These allow more modifications than I would need, but I thought it will help in the future if it is more flexible.

[william-ferguson-au]

Thanks @F43nd1r excellent addition.