benchmarks/netperfmeter: Update to 2.0.0

Improved data processing examples and plotting scripts so introduce R/CRAN
dependencies.
Proper registration of file type for NetPerfMeter output files,
including desktop icons so need for GraphicsMagick, pdf2svg, and
GhostScript during the build, as well as usage of desktop-file-utils.
Update maintainer's email.

Changelog: https://www.nntb.no/~dreibh/netperfmeter/index.html#latest-news

PR: 291927
Approved by: submitter is maintainer