Software quality checklist evaluation for 5/5 FAIR score

See the description in the equivalent issue on cfdm, NCAS-CMS/cfdm#131 for context. In the case of cf-python, the evaluation tool currently reports the following (note I added a small config. file so the tool recognises that cf-pytohn is on Zenodo):

$ howfairis https://github.com/NCAS-CMS/cf-python
Checking compliance with fair-software.eu...
url: https://github.com/NCAS-CMS/cf-python
(1/5) repository
      ✓ has_open_repository
(2/5) license
      ✓ has_license
(3/5) registry
      × has_ascl_badge
      × has_bintray_badge
      ✓ has_conda_badge
      × has_cran_badge
      × has_crates_badge
      × has_maven_badge
      × has_npm_badge
      ✓ has_pypi_badge
      × has_rsd_badge
      × is_on_github_marketplace
(4/5) citation
      ✓ skipped (reason: cf-python is cited on Zenodo and a README badge links to the citation, but that is not picked up by the howfairis compliance checker because the badge in question is a generic website badge linking to the Zenodo page rather than a formal Zenodo badge, purely so the badge colour could be changed to be consistent with our other references.)
(5/5) checklist
      × has_core_infrastructures_badge

Calculated compliance: ● ● ● ● ○

Expected badge is equal to the actual badge. It's all good.

Start by reading the equivalent issue NCAS-CMS/cfdm#131 and rerunning the howfairis command shown for cf-python. Inspect the added configuration file and the README badge links, then determine which failed checks can be addressed; done means the evaluation reaches the intended 5/5 FAIR score.