Prepare to release 3.1.3. (dart-archive#229)

* Prepare to release 3.1.3.

* Remove old file.

Wrap `as` expressions with parens (dart-archive#214)

Closes #213

change version to 3.1.0 (dart-archive#211)

Bump version to 3.1.0

Fix build_runner crashes. (dart-archive#198)

Bump for source_gen. (dart-archive#196)

Prepare to release 3.0.1 (dart-archive#193)

Prepare to publish. (dart-archive#186)

Remove deprecated code and classes. (dart-archive#182)

Prepare to publish 2.4.0 (dart-archive#178)