[GH-4] Removed all non-generic dependencies, and added some more utilities.
[GH-4] Added a recipient class for dealing with various kinds of recipient.
[GH-4] Removed the Spring from ShivaMailException.
[GH-4] Removed all the obsolete tests.
[GH-4] Turned ShivaMailConfig into an interface.
[GH-4] Defined the interfaces for mail content storage/retrieval.
[GH-4] Added in a couple of static variables.
[GH-4] Simplified the main ShivaMail service interface more.
[GH-4] Adding in a provider definition for retrieving stored email styling.