New Drawer infrastructure, RSS callbacks, and more

-Added listeners to the Async RSS parser to get Feed's details
-Added callbacks to the Async RSS parser to return canceled and error
results
-Started infrastructure to compile a "latest news" Feed, with methods in
class Feed and class FeedList
-FeedListAdapter now uses 2 lists in order to get special items and
headers shown in the Drawer. Complex (2-level) infrastructure allows for
much more complex Drawer structure
-New constructors for Post
-The LunaressHelper class now provides some files to act as inptStream
(from /raw folder)
-The main activity now reads the values for the Feed List but does not
even store them; they are passed straight to the Adapter
-The main activity now has the callbacks for RSS parsed, canceled, and
with errors
-...and discovered the actual power of Javadoc! :D (for now only on the
FeedListAdapter class)