WIP: how to make the installation better
imagej-omero: move subroutines to the top
imagej-omero: use a more robust test for OMERO

We now look for blitz.jar, rather than only a directory called "lib".
imagej-omero: pass OMERO home as script argument

This is better than requiring OMERO_HOME to be set, since setting
OMERO_HOME has other (probably undesirable) ramifications.
imagej-omero: add TODO reminder about IMAGEJ_HOME
Rename imagej-omero to install-imagej

The script is migrating toward more of a focus on simply bootstrapping
an ImageJ installation with OMERO-5.0 update site enabled.
WIP