[ffi] Bump the version and update changelog (dart-archive/ffi#64)

Author: jpnurmi

pkgs/ffi/CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.2.0-nullsafety.1
+
+Adds an optional named `length` argument to `Utf8.fromUtf8()`.
+
 ## 0.2.0-nullsafety.0
 
 Pre-release (non-stable) release supporting null safety.

pkgs/ffi/pubspec.yaml

@@ -1,5 +1,5 @@
 name: ffi
-version: 0.2.0-nullsafety.0
+version: 0.2.0-nullsafety.1
 homepage: https://github.com/dart-lang/ffi
 description: Utilities for working with Foreign Function Interface (FFI) code.