IFD: log with LogService, not SLF4J
CBZip2InputStream: log with LogService, not SLF4J
CBZip2InputStream: tweak javadoc

In particular, there is no CBZip2OutputStream, so remove that note.
Add a TIFF service for work with the TIFF format

For now it is very simple, containing only the differencing routines.
But more functionality can be added later as needed.
TiffParser, TiffSaver: keep a SCIFIO gateway

This is much more convenient for accessing SCIFIO services;
we will need it for the codec and TIFF services in particular.
Use the TIFF service for differencing
TiffCompression: remove obsolete differencing methods

They have moved to the TIFFService.
TiffCompression: get codecs from the codec service

If we don't do this, the codecs (which were previously constructed with
a noargs constructor without ever setting their context) will not have
access to a SCIFIO context, and in particular not be able to log
anything without throwing an NPE.
WIP: LOGGER -> log()