Merge pull request #854 from rleigh-dundee/cpp-omexmlmetadata

cpp: Add OMEXMLMetadata template
Update develop submodules

Repository: openmicroscopy/bioformats
Already up-to-date.

Generated by BIOFORMATS-5.1-autogen-docs#9 (http://ci.openmicroscopy.org/job/BIOFORMATS-5.1-autogen-docs/9/)