Register a protocol handler that accepts transactions

[pixelspark]

Allow other web apps to generate transactions and submit them to your (preferred) Catena instance for submission.

Register:

catena:propose/XXXX (where XXXX is an unsigned transaction as JSON as Base64)

See:

• https://caniuse.com/#feat=registerprotocolhandler (it only works in FF+Chrome at this point)
• Howto: https://developer.mozilla.org/en-US/docs/Web/API/Navigator/registerProtocolHandler/Web-based_protocol_handlers