Rolled dev version to only sdk ^2.0.0

pubspec.yaml

@@ -1,16 +1,16 @@
 name: epub
-version: 1.3.2
+version: 1.3.2+dev
 author: Colin Nelson <[email protected]>
 description: Epub Parser for Dart. Suitable for use on the Server, the Web, or in Flutter 
 homepage: https://github.com/orthros/dart-epub
 environment:
-  sdk: ">=1.24.0 <3.0.0"
+  sdk: "^2.0.0"
 dependencies:
   async: ">=1.8.0 <2.1.0"
-  archive: "^1.0.33"
+  archive: "^2.0.0"
   xml: ">=2.6.0 <4.0.0"
   image: ">=1.1.33 <3.0.0"
   dart2_constant: ^1.0.1
 dev_dependencies:
-  test: "^0.12.0"
+  test: "^1.0.0"
   path: "^1.5.1"