[Feature Request]: Make Document Properties Work with Substitutions

[pburrows]

Problem to solve I want to be able to specify template fields in the file properties (document Title, Tags, Comments, Author, Subject, Company, etc....)

Proposed solution Just let normal replacements work in file properties

Describe alternatives you've considered Haven't really thought of any. Maybe use some other library to edit the document after it's been created?

Additional context Nothing specific