Rename the package name/groupId of the cpptasks-parallel dependency

We just renamed the package name and the groupId of cpptasks-parallel
for the purpose of deploying it to Maven Central. This has been
accomplished successfully, too, so let's use the new and shiny,
just-released cpptasks-parallel version 1.1.1.

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