Do not override managed dependency version

It is pom-fiji's job to declare what dependency versions are current in
the Fiji projects.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Remove the unneeded ImgLib1 dependency

We got rid of all the ImgLib1 usage in SPIM Registration, so it is time to
move on now.

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