Allow --java-help as argument to display the Java help

OME-DCO-1.1-Signed-off-by: Sebastien Besson <seb.besson@gmail.com> (github: sbesson)
Test --java-help argument as part of the CLI import unit tests

OME-DCO-1.1-Signed-off-by: Sebastien Besson <seb.besson@gmail.com> (github: sbesson)
Use e.g. rather than ex. across the board

OME-DCO-1.1-Signed-off-by: Sebastien Besson <seb.besson@gmail.com> (github: sbesson)
Fix advanced help alignment

OME-DCO-1.1-Signed-off-by: Sebastien Besson <seb.besson@gmail.com> (github: sbesson)
Yet another alignment commit

OME-DCO-1.1-Signed-off-by: Sebastien Besson <seb.besson@gmail.com> (github: sbesson)
Add leading -- to --checksum_algorithm using bin/omero import
Merge pull request #2772 from sbesson/rebased/develop/cli_import_help_another

CLI import help changes (rebased onto develop)