Remove .lock file on server shutdown.

This should be a minimal fix for situations
where FileMaker can't obtain a lock on the .lock
file in ManagedRepository.
Update the "No FS!" message.
Try to overtake .lock file.
Make ImportLibrary error message universal.
Don't try/catch where it's not needed.
Fix LegacyRepositoryUnitTest.java.
Add unit test for repository takeover.
Make sure to use absolute path.
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 2391 (Imagej omero (rebased onto develop))
merge develop -D org: PR 2411 (Update develop submodules)
merge develop -D org: PR 2435 (cpp: RTypesI: use static locals in place of duplicated globals)
merge develop -D org: PR 2550 (Avoid upscaling of bird's eye image)
merge develop -D org: PR 2560 (for-loop fix removes 'undefined' from reset dialog. See #12301)
merge develop -D org: PR 2612 (Add wsgi.py for OMERO.web (develop))
merge develop -D org: PR 2624 (nginx config template improvement)
merge develop -D org: PR 2686 (clear sessions)
merge develop -D org: PR 2688 (Use a global HDF5 lock (trac: 10464))
merge develop -D org: PR 2690 (Roi clean up develop)
merge develop -D org: PR 2691 (Tag import (rebased onto develop))