Kepler magic add additional feature_type values to usage docs

[kieranross89]

Minor update to the Kepler usage documentation to include additional feature_type values that can be used to plot data that utilises British National Grid (BNG).

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[milos-colic]

@kieranross89 thanks for the PR, can you please sing the CLA above? Then I can merge the PR. Thanks!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f425ba5) 93.86% compared to head (a38b94d) 93.86%.
Report is 17 commits behind head on main.

Additional details and impacted files

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  Coverage   93.86%   93.86%           
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  Files         241      241           
  Lines        6241     6241           
  Branches      108      108           
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  Hits         5858     5858           
  Misses        383      383           

[kieranross89]

@kieranross89 thanks for the PR, can you please sing the CLA above? Then I can merge the PR. Thanks!

It appears to have been signed but the recheck option is not picking it up

[kieranross89]

@milos-colic still not getting the CLA to pick up that it has been singed. As far as I can tell my side it appears okay?

[milos-colic]

@kieranross89 we can use comments hear as acknowledgement of CLA by you. Not sure why the plugin isnt picking it up.