Remove imglib2-scripting code

A while back, it migrated to its own repository:
  https://github.com/imglib/imglib2-script

This scripting code came back recently due to the merge of a rather old
topic branch. The new package (net.imglib2.script.algorithm.integral),
and related test code being removed here, has all been migrated to the
imglib2-script repository.
Remove imglib2-ops project

It migrated into the ImageJ OPS project as deprecated code:
https://github.com/imagej/imagej-ops/commit/a332184e6014567f47a14276c419f4ac3a0172f6

The goal is to fully replace the functionality of ImgLib2 OPS with that
of ImageJ OPS, according to its new and improved paradigm. And in the
meantime, those needing the old codebase can add a dependency on
net.imagej:imagej-ops to retain full backwards compatibility.
Migrate imglib2-ui to its own repository

See: https://github.com/imglib/imglib2-ui
Migrate imglib2-realtransform to its own repository

See: https://github.com/imglib/imglib2-realtransform
Remove algorithms components

As discussed at the October 2014 ImgLib2 hackathon in Madison, they have
migrated to their own Git repositories:

* https://github.com/imglib/imglib2-algorithm
* https://github.com/imglib/imglib2-algorithm-fft
* https://github.com/imglib/imglib2-algorithm-gpl
Remove imglib2-meta component

It migrated into imagej-common. Source at:

https://github.com/imagej/imagej-common

As discussed at the October 2014 ImgLib2 hackathon in Madison, the
imglib2-meta component is being merged into imagej-common, because:

* It simplifies the dependency hierarchy of ImageJ2-based projects.
* It will facilitate simplification of the relevant class hierachies,
  particularly net.imglib2.meta.ImgPlus vs. net.imagej.Dataset.
Convert imglib2 core to a single-module project

This repository is now a single-module project containing ImgLib2
core. Each other component has been split to its own Git repository.

This updates the POM to extend the standalone pom-imglib2 parent. We
no longer need to declare versions, since they are managed. We no
longer need several configuration blocks, since they are inherited.
Merge branch 'component-split'

This converts the imglib2 repository into a single-module project
for the core imglib2 library. Other components have been split
out into their own respective repositories, analogous to how
other SciJava software projects have been structured (see also
the scijava, scifio, imagej and fiji organizations on GitHub).