v0.9.1

• Fixed a Rubiniux bug in synchronization object
• Fixed all interpreter warnings (except circular references)
• Fixed require statements when requiring Atom alone
• Significantly improved ThreadLocalVar on non-JRuby platforms
• Fixed error handling in Edge Concurrent.zip
• AtomicFixnum methods #increment and #decrement now support optional delta
• New AtomicFixnum#update method
• Minor optimizations in ReadWriteLock
• New ReentrantReadWriteLock class
• ThreadLocalVar#bind method is now public
• Refactored many tests