Updated JRuby optimizations in AtomicLong.
Merge branch 'atomic-jruby' of github.com:jdantonio/concurrent-ruby
Fix AtomicFixnum.
Merge branch 'master' of github.com:jdantonio/concurrent-ruby

Conflicts:
	lib/concurrent/atomic.rb
	spec/concurrent/atomic_spec.rb
Merge branch 'master' into better-docs