New caching Column for general Table

This adjusts the current "general" table creation code to include a new
"caching" header and also provides an upgrade path for an installation
that already has a "general" table to have the "caching" column added.
Expose "caching" Value from config Module

Adds an assignment from the resulted row from the general table so that
other modules using the config module will have access to the "caching"
value.
Configuration Database and Form Wiring

Adds serialization and deserialization between the new "caching" column
in the database and the on-screen configuration form.