fix release instructions,

mention `serde` feature in README;

CONTRIBUTING.md

@@ -15,9 +15,9 @@ When we're ready to release, a project owner should do the following:
 
 - Create(checkout) a release branch (naming convention `release/vX-Y-Z`);
 - install or update "cargo release" (via `cargo install cargo-release`);
-- `cargo release minor --no-dev-version -vv --dry-run` if you intend to bump a minor version 
+- `cargo release minor --no-dev-version -vv` if you intend to bump a minor version 
   or change `minor` to `major` to bump a major version, `patch` to bump a patch/hotfix version 
-- check the output and run it without `--dry-run` to actually execute it(make sure that you have api token from `crates.io`, otherwise run `cargo login` first);
+- check the output and run it with `--execute` to actually execute it(make sure that you have api token from `crates.io`, otherwise run `cargo login` first);
 - Merge release branch into develop
 - Merge release branch into master
 - Make a github release

README.md

@@ -19,6 +19,9 @@ let data = data.mapped(|x|x*2);
 assert_eq!(data, [2u8,4].into());
 ```
 
+## Crate features
+- optional(non-default) `serde` feature that adds serialization to `BoundedVec`.
+
 ## Changelog
 See [CHANGELOG.md](CHANGELOG.md).