stable null safety release (#45)

CHANGELOG.md

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 760802e..43f4dd0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 3.0.0
+
+* Stable null safety release.
+
 ## 3.0.0-nullsafety.0
 
 Pre-release for the null safety migration of this package.

pubspec.yaml

diff --git a/pubspec.yaml b/pubspec.yaml
index b41eb15..f0aff73 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: convert
-version: 3.0.0-nullsafety.0
+version: 3.0.0
 description: >-
   Utilities for converting between data representations.
   Provides a number of Sink, Codec, Decoder, and Encoder types.
@@ -9,17 +9,9 @@
   sdk: '>=2.12.0-0 <3.0.0'
 
 dependencies:
-  typed_data: ^1.3.0-nullsafety.5
+  typed_data: ^1.3.0
 
 dev_dependencies:
-  charcode: ^1.2.0-nullsafety.3
-  pedantic: ^1.10.0-nullsafety.3
+  charcode: ^1.2.0
+  pedantic: ^1.10.0
   test: ^1.16.0-nullsafety.9
-
-# Because these packages depend on the pre-v3 version of this package
-dependency_overrides:
-  analyzer: 0.40.6
-  crypto: 2.1.5
-  shelf_static: 0.2.8
-  test: 1.16.0-nullsafety.9
-  web_socket_channel: 1.1.0