Merge pull request #47493 (add roccat-tools)

This adds roccat-tools and one required dependency (libgaminggear),
which I had laying around since June 2016 but never submitted upstream
until now.

The tools are required if you want to configure one of the hardware
devices from the manufactorer ROCCAT.

Builds for both have been tested against i686-linux, x86_64-linux and
aarch64-linux.