Added basic Bitcoin cash support

[programizer]

@bountysource fixes #1136

Still uses old Coinbase API and not yet Coinbase Commerce API.

[programizer]

@kaiansaari Despite the warning banner that used to be on the Coinbase API docs, old API versions still seem to work. So accepting this pull request should actually suffice to support Bitcoin cash on Bountysource. To recieve the payments: Just create a new API key and secret in you regular Coinbase account (https://www.youtube.com/watch?v=Sq_neUUm2u4) and click the bitcoin cash checkbox. After that, add your API key and secret to the .env file in the top level bountysource-core folder on the production server.

[programizer]

Seems to have been solved otherwise...

[eljefuri]

@programizer How was it solved? I do not see any crypto support on the live production bountysource.com at this time? Has it not been updated?

[programizer]

@eljefuri Well, they seem to support their own CanYa Token, now, and also at least Ether... See here, for example:
https://www.bountysource.com/issues/60720231-make-cancelled-salt-sponsorhips-resumeable
https://www.bountysource.com/issues/54370243-keyboard-shortcuts-collapse-tree-and-create-spline
https://www.bountysource.com/?category=crypto
I dont know if they want to support bitcoin cash as well, but even if, probably some other way. Maybe you could start your own fork on your own website when removing the branding... Im not a lawyer though...

[CLAassistant]

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[XVilka]

For those who are still curious in BCH bounties - there is an open-source and free of charge alternative, that supports various cryptocurrencies and allows to set bounties on GitHub issues - jollheef/donate.

This is how it looks in the GitHub issue