Implemented Operation Next
Updated Observable API
Renamed variable
Merge remote-tracking branch 'mairbek/next-new' into next-review
Add unit test testNoBufferingOrBlockingOfSequence

As part of reviewing the code I added another unit test.
don't throw exception on iterator.hasNext()
Merge pull request #166 from benjchristensen/next-review

Review of Next Operation
0.5.4
0.5.5-SNAPSHOT
Unsubscribe behavior.

Adding correct unsubscribe behavior to the example so it models what real implementations should be doing.
Also added comments around the synchronous observable to make clear that it 'firehoses' and will not unsubscribe regardless of a take operator saying it wants less than the 50 it will send.