We've run into problems because we weren't maintaining older
deliverable files as we extended the schema. This change moves schema
validation out of the main validation command so it runs as a separate
step and processes all deliverable files by default. The more complex
validation rules are still only checked for files being modified in a
given commit.
Change-Id: I4b69ca3c59da6606cf2b27d05c8846223d52998a
Signed-off-by: Doug Hellmann <doug@doughellmann.com>