Week #2: Preference Handling

In the last week, these things have been done:
* Setting Default Modes
* Setting Modes for a Contact
* Setting Modes for a Chat Session
* Setting Archiving Method Preferences
* Client Enables/Disables Automatic Archiving

So, the preference handling is mostly done, far ahead of the schedule.

The next step:
* Automatic Archiving. Grab messages and store them.