Add utility methods to deal with lists of metadata values

See #9928.
Use add*MetaList methods to ensure that metadata keys are sorted correctly

Fixes #9928.
Merge remote-tracking branch 'origin/develop' into 9928

Conflicts:
	components/bio-formats/src/loci/formats/in/LIFReader.java
	components/scifio/src/loci/formats/FormatReader.java
Remove duplicate hashtable flattening logic
Fix a few bugs in metadata list handling
Zeiss LSM: use metadata lists in a few more places
Slidebook: use metadata lists in one more place
Merge pull request #329 from melissalinkert/9928

Sort original metadata keys ending with an index