ExporterI: set tile size for exported files to 128x128

This prevents the OME-TIFF writer from writing each row of pixels as a
separate strip, which should improve performance upon re-importing the
exported file.

See ticket #11850.
Delete example uses CmdCallback
Link FileAnnotation by link creation
Cleanup login details etc
Started work on Java delete example
fixing UnicodeEncodeError when searching, close #11941
/OriginalfileAnnotationLink -> /OriginalFileAnnotationLink
Use monkeypatch for bin/omero config envvar unittests
Add subcommands help tests to test_prefs.py
Add failing tests for bin/omero config drop and set subcommands
Add first implementation of remove and append subcommand with unit test
Fix remove with only one item and add error handling in append/remove
Add unit tests for failing append/remove calls
Optimize duplicate line
Only support file input for omero config set subcommand
Review failing append/remove unit tests
Fix omero config subcommands description by using parser.add()
Add append and remove to the subcommand list in test_prefs.py
Fix description and help of various omero config commands/arguments
Expand "standard in" to "standard input"