Map globals over domain.

I modified the schema and split the casaa_plugin_registry table into two different tables:

casaa_plugin_registry: stores the module's filename and the module's display name
casaa_plugin_domain: stores the module's status and global variable for the set domain.

i've modified the globals section to accept settings per domain. We'll need to do some more clean up and testing through the execution phase as not all functions have been updated to be compatible with the new schema.

also, i'll need to build a update path to accommodate for the schema changes.

also, we'll need to alter the upgrade paths for each plug-in to comply w/ the new schema.

I've mostly completed the conversion. The last thing to do is check that the different settings for each domain is coming across for each plug-in per domain.

i will work with kbasarab to confirm that this is working for all elements.