FormatReader: clear the 'core' variable

Suggested by Curtis Rueden.
Zeiss CZI: tidy up metadata hashtable keys
Fix the Imaris metadata page
Make sure that SizeZ/SizeC/SizeT are set for single-file exports
Deltavision: make sure that the DetectorSettings.ID is set

See QA #4877.
Metamorph: look for the channel count in one more place

Reported by Stéphane Dallongeville.
Remove hard dependency on log4j from core Bio-Formats/SCIFIO
Remove loci.formats.utests.tiff.OMETiffWriterTest

All this test does is check for open file handles; we now have much more
comprehensive tests that cover the same thing (and without depending
upon log4j).
Remove commented-out log4j code from the ome-io component

These classes are beyond obsolete anyway, and will likely be removed in
the next major release.
ICS writer: fix support for writing RGB images

Reported by Harri Jäälinoja:

http://lists.openmicroscopy.org.uk/pipermail/ome-users/2013-February/003529.html
Merge remote-tracking branch 'origin/dev_4_4' into logging

Conflicts:
	components/scifio/test/loci/formats/utests/tiff/OMETiffWriterTest.java
Merge pull request #368 from melissalinkert/logging

Remove hard dependency on log4j
Merge pull request #373 from melissalinkert/sprint5-bug-fixes

Sprint5 bug fixes