zcash_note_encryption: Clean up changelog and readme

We no longer depend on the previously-mentioned dependencies.


Extracted from: 9a010d42ff

CHANGELOG.md

@@ -13,7 +13,6 @@ and this library adheres to Rust's notion of
 
 ### Changed
 - MSRV is now 1.56.1.
-- Migrated to `group 0.13`.
 - `zcash_note_encryption::Domain` now requires `epk` to be converted to
   `Domain::PreparedEphemeralPublicKey` before being passed to
   `Domain::ka_agree_dec`.

README.md

@@ -22,16 +22,6 @@ Licensed under either of
 
 at your option.
 
-Downstream code forks should note that 'zcash_note_encryption' depends on the
-'orchard' crate, which is licensed under the
-[Bootstrap Open Source License](https://github.com/zcash/orchard/blob/main/LICENSE-BOSL).
-A license exception is provided allowing some derived works that are linked or
-combined with the 'orchard' crate to be copied or distributed under the original
-licenses (in this case MIT / Apache 2.0), provided that the included portions of
-the 'orchard' code remain subject to BOSL.
-See https://github.com/zcash/orchard/blob/main/COPYING for details of which
-derived works can make use of this exception.
-
 ### Contribution
 
 Unless you explicitly state otherwise, any contribution intentionally