add example of adding extra model fields to IceMapper
Merge pull request #570 from bpindelski/rebased/dev_4_4/11677-javatest

Add group and test method execution doc (see #11677) (rebased onto dev_4_4)
merge dev_4_4 -D org -I include -E exclude: PR 559 (remind that model changes may affect IceMapper (rebased))
merge dev_4_4 -D org -I include -E exclude: PR 571 (Document latest OMERO.matlab functions (rebased onto dev_4_4))