Merge #557: Add additional changelog entry

494b07a Add changelog entry (Tobin C. Harding)
d0c4af0 Add newline after docs heading (Tobin C. Harding)

Pull request description:

  ~Bump version to 0.25.1 ready to release~ Add changelog entry for the recently fixed unsoundness issue.

  Patch 1 is an annoyingly trivial fix to docs.

ACKs for top commit:
  apoelstra:
    ACK 494b07a

Tree-SHA512: 8de8d735d3dce06683ec8e66b78b966406f42ea0a8e679e8e82143a984251addd74bea3658cc63ba9d9eada3517e461e9c28085d5261d9c0db2dceb15a8cbcc2

CHANGELOG.md

@@ -1,5 +1,6 @@
-# 0.25.0 - 2022-11-22
+# 0.25.0 - 2022-12-07
 
+* [Fix soundness issue with `preallocated_gen_new`](https://github.com/rust-bitcoin/rust-secp256k1/pull/548)
 * Use type system to [improve safety](https://github.com/rust-bitcoin/rust-secp256k1/pull/483).
 * [Change secp256k1-sys symbol names to 0_6_1](https://github.com/rust-bitcoin/rust-secp256k1/pull/490).
 * [Introduce `rustfmt`](https://github.com/rust-bitcoin/rust-secp256k1/pull/499) to the codebase.

src/context.rs

@@ -311,6 +311,7 @@ unsafe impl<'buf> Context for AllPreallocated<'buf> {
 /// memory that must outlive `'a`
 ///
 /// # Safety
+///
 /// This trait is used internally to gate which context markers can safely
 /// be used with the `preallocated_gen_new` function. Do not implement it
 /// on your own structures.