feat(farmer-app): dynamic svg skin tones

[chrismclarke]

Is your feature request related to a problem? Please describe.
As the app is used in different countries we may want to try and alter certain visual assets to align more closely with local contexts. Some of this will happen via generating entire new icon sets, however some improvements might also be made by making small adjustments to existing images, such as skin tone used in icons.

Describe the solution you'd like
Part research/discovery, part proof-of-concept. Try to determine whether it is possible to use css classes to dynamically adjust svg images to provide a variety of possible skin-tone options and any other localisations that may be useful.

Describe alternatives you've considered
Whilst we could generate new icon sets for all contexts this will quickly become hard to manage and be quite resource intensive.

Additional context
A few potential starting points for research

• https://medium.com/@kellyleigh/designing-an-inclusive-skin-tone-pale-84481cb01913
• https://css-tricks.com/changing-emoji-skin-tones-programmatically/
• https://louisem.com/466136/skin-tone-hex-codes

[chrismclarke]

Some initial investigation work will be carried out by Denis