OTL Book Update

A minor update of the “OmniThreadLibrary Book” has been released.
Changes:

• Adapted to the OmniThreadLibrary 3.02 release.
• Documented background worker initializers and finalizers.
• Documented Async/Await abstraction.
• Fixed minor problems found by [jachguate].

Update [2012-10-09]: Russian translation has also been updated.
Update [2012-10-12]: Spanish translation has been released.