[jpackage] Customize msi installer

[Tobias Diez]

Hi,

after experimenting with jpackage for creating a msi installer, I would like
to suggest the following improvements:

1. Set the ARPPRODUCTICON property, that controls the icon displayed in
Add/Remove Programs for your application.
https://wixtoolset.org/documentation/manual/v3/howtos/ui_and_localization/co
nfigure_arp_appearance.html
e.g: <Property Id="ARPPRODUCTICON" Value="DesktopIcon.exe" />
(btw: it's strange that the icon ids end on exe)

2. Make it possible to customize the appearance of the installer. At least
make it possible to specify WixUIBannerBmp and WixUIDialogBmp. I guess most
people want to replace the default icons with their own ones.
https://wixtoolset.org//documentation/manual/v3/wixui/wixui_customizations.h
tml

Best
Tobias