[dev] Abstract vs. Base

[Chuck Hagenbuch]

Quoting Jan Schneider <jan at horde.org>:

> Done. I left out the classed in Adapter/Abstract/ for now, because  
> they don't seem to be properly named in a different sense.
>
> Even if we rename them to Base, they should be  
> Horde_Db_Adapter_Schema_Base not Horde_Db_Adapter_Base_Schema,  
> right? That would clutter the Db/Adapter/ directory though, because  
> the files would go into Db/Adapter/*/Base.php instead of  
> Db/Adapter/Base/*.php

The reason the naming is a bit backwards (Base_Schema instead of  
Schema_Base) is to keep the adapter-related files together. If we  
change it to Schema_Base, then the mysql-specific files would be  
scattered among each directory.

-chuck