Java3D dependencies should always be in the 'provided' scope

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Bump the last two non-TrakEM2 components to release versions

Now the TrakEM2-related things only need to be moved to their own parent
POM and we're ready for the next beta release version of pom-fiji.

Note: We did not reach our goal of fully reproducible builds yet: some
of the releases we cut *still* depend on -SNAPSHOT versions. This is
something we will need to fix one by one, and the maven-enforcer-plugin
(which is configured by the pom-scijava version we depend on
transitively) will help with that.  Signed-off-by: Johannes Schindelin
<johannes.schindelin@gmx.de>
Tell git to ignore Eclipse metadata
Extend pom-imagej 5.0

This brings in the latest versions of SciJava components,
particularly the release version of imglib2.
Remove superfluous version declaration

The scijava-maven-plugin's version is managed in the parent.
Remove superfluous distributionManagement section

You can pass the -Pdeploy-to-imagej flag if you want to deploy to there.
Remove superfluous maven-compiler-plugin version

It is managed in the parent.
Declare all version properties as release versions

At the time of this writing, some of these projects have not actually
been released at those versions. Hence, it is a preemptive version bump.
Remove obsolete projects

These version numbers are no longer declared, and hence
the version management declarations are not useful.
Bump fiji-lib to 2.1.0

The 2.0.1 release is invalid.
Bump 3D_Viewer version to 3.0.0
Bump to next development cycle

Signed-off-by: Curtis Rueden <ctrueden@wisc.edu>
Move TrakEM2 and related projects to their own parent POM

In line with the recent push for Reproducible Builds and a better
structuring, let's let TrakEM2 manage its Bill of Materials in its own
POM.

For further rationale, see http://fiji.sc/Reproducible_builds and
http://fiji.sc/Bill_of_Materials, respectively.

This is an emergency bug fix for pom-fiji version 5.0 (the Pull Request
should have blocked the release until the discussion was resolved).

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