Advice about that: I had the same question to me as regards the HPCBIOS headers:
it is simpler and more convenient to maintain a single version of the header across all project contents
and that also allows consistent maintenance of it, when you need it.
(ie. the header should not substitute the version control system which does a better job for this).

Technically, it is not wrong as long as they belong to the same project effort... 
(proof: you can have 0-sized templates for whatever future packages and work)