Move cast from test class into the correct spot

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
POM: update to the ImgLib2 2.0.1 release

This makes the necessary code changes to account for backwards
incompatibilities.

It also updates several dependencies to their latest versions,
and removes the obsolete imglib2-ops dependency.
Avoid using SCIFIO in imagej-common's tests

Curtis says this is bad, bad, bad.

Actually, he said that the hierarchy is being restructured and that
imagej-common should be upstream of both SCIFIO and ImageJ-OPS, and it
all makes sense, but that is not half as funny a commit message.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
WIP