Merge pull request #962 from rleigh-dundee/cpp-formatreader-interface

C++: Add FormatReader interface and associated classes
merge develop -D org: PR 857 (Initial support for Zeiss .lms files)
merge develop -D org: PR 859 (Assorted metadata/tile parsing fixes)
merge develop -D org: PR 950 (Cellomics: a few fixes for single-file datasets)
merge develop -D org: PR 959 (CZI: make sure that SubBlocks are correctly initialized in openBytes (rebased onto develop))