f mention new serialization policy in contributing

Author: TheBlueMatt

CONTRIBUTING.md

@@ -88,10 +88,11 @@ be covered by functional tests.
 When refactoring, structure your PR to make it easy to review and don't
 hesitate to split it into multiple small, focused PRs.
 
-The Minimum Supported Rust Version (MSRV) currently is 1.41.1 (enforced by
-our GitHub Actions). Also, the compatibility for LDK object serialization is
-currently ensured back to and including crate version 0.0.99 (see the
-[changelog](CHANGELOG.md)).
+The Minimum Supported Rust Version (MSRV) currently is 1.48.0 (enforced by
+our GitHub Actions). We support reading serialized LDK objects written by any
+version of LDK 0.0.99 and above. We support LDK versions 0.0.113 and above
+reading serialized LDK objects written by modern LDK. Any exepected issues with
+upgrades or downgrades should be mentioned in the [changelog](CHANGELOG.md).
 
 Commits should cover both the issue fixed and the solution's rationale. These
 [guidelines](https://chris.beams.io/posts/git-commit/) should be kept in mind.