Add slf4j dependencies to OMERO.matlab toolbox
Add getOmeroJars() function to list toolbox JAR dependencies

Include a conditional inclusion of the slf4j-api and slf4j-log4j12 JAR files
for versions of MATLAB older than R2011b.
Fix javarmpath() command in unloadOmero()

For some reasons, javaaddpath() supports a cell array while javarmpath()
does not. This commit unifies the behavior by passing the jars as multiple
elements to both functions in loadOmero() and unloadOmero().
Apend omero_client to the list of JARs to load
Use cellfun to add/remove JARs to the dynamic Java class path

For some unknown reason, javaaddpath(omeroJars{:}) does not work on the CI
node (effectively adding the first JAR only). This commit should fix the behavior by encapsulating the javarmpath/javaddpath calls using cellfun().
Ship log4j.jar with OMERO.matlab and add it conditionally to the Java path

This commit refactors the getOmeroJars() logic to rely on the Java class path
rather on hard-coded versions of MATLAB. The log4j and slf4j dependencies are
assessed independently.
Merge pull request #2236 from sbesson/rebased/develop/matlab_slf4j

OMERO.matlab slf4j dependencies (rebased onto develop)