Updates to multiplexer_test.dart
Rename multiplexer_test to handler_test.
Merge with latest changes.
Merge pull request #205 from alxhub/master-v0.2

Refactor and rename multiplexer_test to handler_test and include in all_tests.dart.
Working on addendum tests.
isPrimary now takes an AssetId instead of an Asset.
Merge pull request #206 from alxhub/fix-barback

Barback version update changed isPrimary() - now takes an AssetId instead of an Asset
Merge remote-tracking branch 'upstream/master-v0.2' into master-v0.2
Addendum tests passing.
Merge pull request #207 from alxhub/master-v0.2

Move sendParams to the .streamy.yaml file, and make addendum_test pass with them.
Consolidate & fix raw and wrapper tests
Split marshalling tests from entity tests
Move base tests to separate file
Merge pull request #203 from yjbanov/marshaller-tests

Marshaller tests
Reinstate request test
Organize imports in all_tests.dart
Reinstate transforms test
Remove reference to the deleted multiplexer_test.dart file