celluloid/celluloid — pull request #254 by benlangfeld (2013-05-13 15:00:14+00:00)
Title: Give threads a default role of nil for BC

@halorgium Introduced thread roles in 1c748525d425eea80c11f8de070b44e9b067eaf3 but this is not backwards compatible with 0.14.0, and makes it difficult to use ThreadHandle in third-party libs before 0.15.