Add --cpu flag to generate

[mimischi]

Fixes #66.

Changes made in this pull request:

• mdbenchmark generate now accepts --cpu / --no-cpu, as well as a --gpu / --no-gpu options. If given both --cpu and --gpu, it will generate both benchmarks at once. The default is --cpu and --no-gpu.

PR Checklist

• Added changelog fragment in ./changelog/ (more information)?
• Issue raised/referenced?

[codecov]

Codecov Report

Merging #69 into develop will increase coverage by 0.06%.
The diff coverage is 100%.

@@             Coverage Diff             @@
##           develop      #69      +/-   ##
===========================================
+ Coverage    96.47%   96.53%   +0.06%     
===========================================
  Files           13       13              
  Lines          567      578      +11     
===========================================
+ Hits           547      558      +11     
  Misses          20       20

Impacted Files	Coverage Δ
mdbenchmark/generate.py	100% <100%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 95fb6fb...ba71a6c. Read the comment docs.