SingleRequestTransformer working in tests
Merge branch 'master' into short-lived-streams

Conflicts:
	test/all_tests.dart
Move transformers_test into streamy_test.
SingleRequestTransformer -> OneShotRequestTransformer
Merge pull request #11 from alxhub/short-lived-streams

SingleRequestTransformer filters a Streamy stream and only returns results from the first initial request/response cycle, then closes the stream.
Improper use of Key instead of K in ComparableMap.
Take toString() of closure when throwing ClosureInEntityException.
Merge pull request #13 from alxhub/checked-mode-fixes

Some fixes to get tests working --checked mode.