Allow build_runner 0.10.0

• Allow build_runner 0.10.0.

Fixes; allow built_collection 4; ignore unnecessary_const/new

• Improve generation for operator==, don't use dynamic.
• Improve error message and documentation for missing builder factory.
• Allow built_collection 4.0.0.
• Fix code generation stack overflow when there is a loop in serializable types.
• Fix library name output in generation error messages.
• Add ignores for lints 'unnecessary_const' and 'unnecessary_new' to generated code.

Upgrade to source_gen 0.9.0

• Update to the latest source_gen. This generator can now be used with other generators that want to write to .g.dart files without a manual build script.
• Breaking change: The "header" configuration on this builder is now ignored.

Allow SDK 2.0.0

Merge pull request #463 from davidmorgan/bump-sdk

Allow SDK 2.0.0.

More lint ignores; bump quiver version

• Add ignores for lints 'lines_longer_than_80_chars' and 'avoid_catches_without_on_clauses' to generated code.
• Bump version of quiver.

Bump versions of build_runner, build_config and shelf.

Merge pull request #449 from davidmorgan/fix-build

Bump versions of build_runner and build_config.

Fix violations of prefer_equal_for_default_values lint.

Merge pull request #448 from davidmorgan/release-5-5-2

Release 5.5.2.

Bump analyzer version

• Bump versions of analyzer, analyzer_plugin.

Set and DateTime serialization; fixes for generics

• Support serializing BuiltSet with StandardJsonPlugin. It's serialized to a JSON list.
• Add Iso8601DateTimeSerializer for use when you want ISO8601 serialization instead of microseconds since epoch.
• Fix code generation when inherited generic fields are made non-generic.

Better error messages, more checking

• Improve error message on failure to deserialize.
• Move check forbidding instantiation with dynamic type parameters from builder to value class. Previously, you could avoid the check by using the generated constructor called _.