Proper enforcement of `r-----` style permissions

Previously, the user's A and W bits were ignored when
it came to creating objects: if logged into the group
anyone could create objects as themselves. With this
addition, strict read-only groups (`r-....`) disallow
any object creation.
Fix typos isReadyOnly
Add ISession.getOpenSessions and EventContext.isReadOnly

See #2265 for when the isReadOnly flag was removed.
We will need to make sure the various cases are taken
into account.
Merge pull request #2162 from dominikl/path_on_import_selection

Bugfix: Image import: File naming settings were ignored
Implemented Mark's suggestions

Fixed missing break; use CollectionUtils; completed if statement with else
merge develop -D org: PR 1960 (Remove cut link 11882)
merge develop -D org: PR 2127 (Working view to email announcements to selected users, groups, email addresses and/or all users)
merge develop -D org: PR 2160 (Warning dialog before deletion of linked images)
merge develop -D org: PR 2161 (Minify viewer media)
merge develop -D org: PR 2165 (Inplace file path)
merge develop -D org: PR 2171 (Added ROI filtering option)
merge develop -D org: PR 2177 (develop: Update upgrade check handling in OMERO.web)
merge develop -D org: PR 2178 (Update develop submodules)
merge develop -D org: PR 2182 (Read only flag)
merge develop -D org

Repository: openmicroscopy/openmicroscopy
Excluded PRs:
  # PR 2163 qidane 'New wavelength changes' (exclude comment)
  # PR 2128 jburel 'Open with develop' (label: exclude)
  # PR 2036 joshmoore 'DSL Map Type' (exclude comment)
  # PR 1385 manics 'Update the OMERO VirtualBox image' (exclude comment)
Already up-to-date.

Merged PRs:
  # PR 1960 will-moore 'Remove cut link 11882'
  # PR 2127 dpwrussell 'Working view to email announcements to selected users, groups, email addresses and/or all users'
  # PR 2160 dominikl 'Warning dialog before deletion of linked images'
  # PR 2161 aleksandra-tarkowska 'Minify viewer media'
  # PR 2165 dominikl 'Inplace file path'
  # PR 2171 dominikl 'Added ROI filtering option'
  # PR 2177 chris-allan 'develop: Update upgrade check handling in OMERO.web'
  # PR 2178 snoopycrimecop 'Update develop submodules'
  # PR 2182 joshmoore 'Read only flag'

Repository: openmicroscopy/bioformats
Excluded PRs:
  # PR 978 berl 'Add writing of .v3draw format for easy loading with Vaa3D.' (user: berl)
  # PR 881 qidane 'New wavelength' (exclude comment)
  # PR 816 melissalinkert 'Add support for multi-channel Volocity Clipping datasets' (label: exclude)
  # PR 528 melissalinkert 'Tile performance improvements for VMS and NDPI' (label: exclude)
Updating 5347672..7e63798
Merged PRs (fast-forward):
  # PR 859 melissalinkert 'Assorted metadata/tile parsing fixes'

Merged PRs:
  # PR 857 melissalinkert 'Initial support for Zeiss .lms files'
  # PR 858 melissalinkert 'Initial support for Veeco AFM data'
  # PR 970 rleigh-dundee 'C++: Add FormatReader implementation'
  # PR 973 rleigh-dundee 'C++: Fixes for the OME-XML model and metadata store interfaces'
  # PR 975 rleigh-dundee 'cpp: cmake: Don't enable -pedantic if it breaks long long use'

Repository: ome/scripts
Already up-to-date.

Repository: openmicroscopy/ome-documentation
Already up-to-date.

Merged PRs:
  # PR 626 pwalczysko 'Add new Squash tutorial and screenshots'
  # PR 701 bpindelski 'Remove paragraph about whitespace and Ice.'

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