Added the Executor based EchoServer.
Refactored the Downloader to use a CopyOnWriteArray instead of cloning the listeners during updateProgress.
Added a very rough draft of the wordcount program.
Fixed a number of issues with the initial draft.
Refactored to use the producer-consumer pattern with custom locking on the counts hashmap.
Refactored Counter to use a ConcurrentHashMap instead of manual locking.
Refactored counter to use a local counts Map that gets merged into the shared one before termination.
Refactored Pages to use XMLStreamReader.
Simplified XML parsing and the Word generator.