43b1ed1b86 Fully encapsulate bitcoinconsensus (Tobin C. Harding)
Pull request description:
The `bitcoinconsensus` crate is not fully under our control because it exposes code from Core, so we cannot guarantee its stability across versions. To make our semver compliance easier we can fully encapsulate the `bitcoinconsensus` crate so it does not appear in our public API.
### Please note that with this applied:
- The `bitcoinconsenus` crate is no longer exported at the crate root
- No `bitcoinconsensus` types appear in our public API
ACKs for top commit:
Kixunil:
ACK 43b1ed1b86
apoelstra:
ACK 43b1ed1b86
Tree-SHA512: 9fc4f01a35396562e980a647784b22667cbd289e45b5c122610d23a1f8bcf0fe8b9c27e33745f14ee010050d4c2d2669b679fb39c7a108e4e86d2c14fd60571a