remove '/' to increase template matching for testing.
don't check @qualifier
fix indents
create root node first

root node template makes <resource> tag and calls <xsl:apply-templates>
within.
make generic template to get identifier element
refactor code to find <identifier>

There should only be one DOI, so no need to call loops
move "dim:dim" template start/end

variables can be declared outside of this template.
fix indents
handle finding non-dim data for datacite

template parse_mets finds datacite data that is not stored in DIM.
add some comments
more indent fixes
move mets_url assignment
move alternate identifiers
parse_mets doesn't need to be its own template
refactor for multiple identical ifs

It makes more sense to just have one master test for package tags vs
file tags.
sizes tags can be moved inside the files-only test
Merge branch 'datacite-work' into datacite-sizes
more massive reorganization to pass validation
refactored blackout.xsl to match DIM2DATACITE.xsl
added sizes metadata to blackout, because why not?