Some fixes to error handling.

The fundamental issue was that exceptions could bubble up past the point where new error handlers were bound. The fix is to wrap thrown exceptions in a container that also provides the exchange.
Some more fixes to error handling.

Don't wrap HandlerExceptions in HandlerExceptions.
Added a clean up of Expression&*.class files

The cleanup should keep the class files from building up over time.
Fixed missing escaped char.
Use a pooled byte buffer allocator.
Set SO_REUSEADDR to true.
Fix the shutdown process.
Close the socket after using it for the config.
Some POM cleanup.
Some work on the intro chapter.

Not complete by far.
Some minor cleanup.
Add some global configuration so that any projects that internally use the Gradle plugins build against the latest source.
Add the first of a few "performance test" projects useful for benchmarking Ratpack.

This one is the simplest (and fastest) possible Ratpack application and is useful for benchmarking the Netty usage.
Merge pull request #57 from beckje01/cleanUpTask

Clean up task
Some tweaks to the cleaning up of expression files (from Springloaded).
Use the project path to identify the runner in IDEA.
Some incomplete Javadoc for Handler.
Minor optimization to avoid creating an error handler per request.
Minor optimization to avoid list creation.
Optimization to avoid list creation.