44d3ec487d Rename Payload::as_bytes to inner_prog_as_bytes (sanket1729)
a446df583c Make Payload non-exhaustive (sanket1729)
6ebc9de252 Introduce WitnessProgram struct and cleanup Address validity invariants (sanket1729)
41652caf05 Introduce is_spend_standard method (sanket1729)
Pull request description:
Fixes#1561.
Highlights:
- Segwitv0 programs with lengths apart from 20 or 32 are invalid `Address` struct. Such Addresses are useless and we should not parse/create them.
- Renamed `is_standard` to `is_spend_standard`.
ACKs for top commit:
apoelstra:
ACK 44d3ec487d
tcharding:
ACK 44d3ec487d
Tree-SHA512: 1ee36f7ea25c65619ddf7d643d025690096876843dbe6fbdf877ce23e88049d79b0bbd78cee6cf4b415bca028b3634bb70c9f52d1098bd90558e6ba7f8731332