Remove commented-out configurations:
* Old versions of cpptasks-parallel.
* Bigpixel-snapshots snapshotRepository.
Remove unnecessary pluginRepository configurations:
* http://duns.github.com/maven-snapshots/
* https://oss.sonatype.org/content/repositories/snapshots/

These repositories does not appear to be necessary in order to built & test the code. Therefore, they should be removed to simplify the configuration.