[RFC] Issue #36 - add approx price

[inkredabull]

#36

@wanderingstan don't know if your culture is to entertain RFC/WIP PRs but here we go...

Checklist:

• Testing (no other component tests??)
• No docs to update

Description:

• Adding approximate price to UI (ListingCard) using cryptocompare per original requirements
• still need to:
  • add caching and/or update for Cryptonator
  • add test for rendered markup
  • ensure always two decimal places
  • incorporate bridge server if so desired (docs?)

Example:

[inkredabull]

Ping @wanderingstan - would love to continue making progress just need a little guidance around what's really essential to get this into mergeable state.

[wanderingstan]

Hey @inkredabull just took a look. Looks like some merge conflicts came up due to other work on develop.

Important: Could you re-submit this as a PR against develop? (I don't think we had our PR messaging clear when you made this one.)

[inkredabull]

Sure @wanderingstan - will rebase against develop.