Enhanced the comments to clearly show how this relates to the Template Method pattern.
Updated the JUnit tests for SimpleAtomicLong.
Clarified several things.
Emphasized "green" checkmarks.
Clarified what the output means.
Yet more clarifications.
Clarified "TODO" comments.
Clarified the diagnosticsEnabled variable behavior and added more pattern-oriented comments.
Added new grading driver.
added SynchronizedQueue.java back.
Merge remote-tracking branch 'upstream/master'