Zeiss CZI: initial modulo support

This required the addition of a few new dimension types to FormatTools.
Modulo: fix length reporting if only the labels were set
Zeiss CZI: populate modulo label data, if available
Update the OME-TIFF reader to read ModuloAlong annotations
CZI: fix plane index assignment
CZI: check channel index before populating ExposureTime
OMEXMLService: fix ModuloAlong annotation population

This fixes how the annotation is structured, so that empty xmlns
attributes are not inadvertantly added.
Merge pull request #781 from melissalinkert/czi-modulo

Add modulo annotation support for Zeiss CZI data