Log Message:
Add ruby-celluloid package version 0.16.0.

Celluloid provides a simple and natural way to build fault-tolerant concurrent
programs in Ruby. With Celluloid, you can build systems out of concurrent
objects just as easily as you build sequential programs out of regular
objects.  Recommended for any developer, including novices, Celluloid should
help ease your worries about building multithreaded Ruby programs.