#13 Preferences Dialog Needs Work

[John Munsch]

The user preferences dialog has options for setting
the proxy but they are currently ignored. The option
needs to be implemented and the value saved/loaded.

After the ability to have different data stores for
the items and channels is available then there is a
tab where the type of store to use needs to be
selectable and additional parameters (like JDBC
connection information) can be provided.