Update pub package description

Merge pull request #127 from davidmorgan/update-description

Release 3.0.1.

Changes for Dart 2

Add new methods that will appear in Dart 2. They are currently not implemented.

This is a breaking change for libraries that implement their own built collections, hence the major version increase. Most users will not need to make any changes.

Revert changes for Dart 2

Changes for Dart 2 will be re-released as v3.0.0.

They don't make any differences for most users, but for libraries that implement their own built collections, the changes were breaking. So they need a major version increase.

Fix changes for Dart 2

Previous release had some issues.

Prepare for Dart 2; add methods to Iterable

They are currently not implemented.

Allow different Set and Map bases

BuiltSet and BuiltMap now allow you to specify the underlying collection type. For example, you can construct a BuiltSet using a SplayTreeSet. This results in a set that is always in sorted order instead of preserving insertion order. Another useful possibility is to use a HashSet, which leads to a random order but improves performance over the default.

See SetBuilder.withBase and MapBuilder.withBase.

Separate interfaces

Split collection classes into abstract interfaces and concrete, private, implementations. This allows new implementations of the interfaces. Note that this change is invisible unless you rely on the exact runtimeType of the collections.

Fix null checking

Fix a bug whereby ListBuilder and MapBuilder allowed nulls to be introduced via map and expand.

Allow quiver 0.26

Merge pull request #109 from davidmorgan/bump-quiver

Allow quiver 0.26.

Make addIterable generic

This allows the types of functions passed in to be inferred. Without this, the analyzer will start to complain unless you type them explicitly.