Fix warning messages, generated by Maven (v3), during build.

* Added missing version numbers for build plugins and dependancies.
* Removed duplicate dependancies.
* Updated obsolete groupId.
* Added minor formatting changes.
Upgrade the build plugins to the latest version.

The report plugins were not modified.

* The configuration of the surefire plugin in the imagemosaic/pom.xml was altered to conform to the requirements of the latest pluigin.
* Inserted some missing groupIds.
* Inserted some missing versions.
* Minor formatting changes.
* Removed some obsolete comments.
Merge pull request #208 from brett-walker/fix-plugin-versions

Fix warning messages, generated by Maven (v3), during build.