This patch refactors how the recieved message processing happens.
We now handle all incoming packets the same. Removed the notification
thread to handle the watchlist packets. This is now done with a
unified plugins architecture that allows different capabilities
via the new plugin structure. All packets sent to us will be
sent through all of the plugins. It's the plugins job to decide what to
do with that packet or ignore it.
Email is no longer a special case for the most part. All email
functions have been migrated to the EmailPlugin, including starting the
EmailThread, which works in the background to check for new emails and
send those to the registered callsign. The EmailPlugin now starts the
EmailThread itself.
All plugins are now build on the new APRSDPluginBase which has a common
set of features. The APRSDPluginBase calls self.setup() upon creation,
which allows all plugins to do whatever they want for initiali startup.
The EmailPlugin uses setup() to start the EmailThread if email is
enabled.
This patch reorganizes the config file layout and options
to make more logical sense as well as make it more readable.
This breaks backwards compatibility.
This patch fixes the email.get_email_from_shortcut. It ensures that
if the lookup isn't found in the shortcut list, it simply returns
the original value. This patch also adds a unit test to specifically
test this function to always return the correct value.
