Drop package qualifier for :USE-PACKAGEd package.
Export odbc-db class.
Update fixme
Remove slots that are handled in base-db now.
Add slot for the client port used by the sql server.
Add generic function to produce db initargs from config options.
Make MAKE-DB a generic function with default methods for most cases.

The default methods for MAKE-DB create an instance, use the new
DB-INITARGS function to produce the right initargs from the config
options, then re-initializes the instance. This means
INITIALIZE-INSTANCE runs twice, so classes should define their own
methods if that causes a problem.
Update example config.
Add a some notes for future work
Update examples to reflect pathname requirement.
Add function to create db object from config data.
Add missing package qualifiers.