Fix balutil handling of DisplayInternalUI

Virtually all changes to parsing BootstrapperApplicationData.xml need to be done in mbacore and balutil.

Also, fix Intellisense for dutil and typos/style in thmutil.
Should only be done when necessary, aka: a Property depends on values set in the .props file. The ideal is that there is just a single .targets import at the bottom. That removes significant complexity possibility. I'd have to look closer to see why the others do it...