fixed UUIDs to write out as ByteBuffer objects.  Tests were passing before as false positives, but final wire level output was incorrect.
* added a new BoxedFloat boxed type to ensure that isFloat() can
  unambiguously detect floats
* added tests around the BoxedFloat type to make sure that we can compare
  against standard JS types by overloading the valueOf()
* forced timer, timed_send, and incr methods to use the new BoxedFloat type
  when setting the rate to the default of rate=1.0
updated example to use streams api
updated default timestamp to convert Date objects to nanoseconds
added docs on using BoxedFloat
renamed heka to heka-node
updated changelog
Merge branch 'dev' into features/new-protobufjs
updated documentation version to 0.6