automatically generate introspective data JSON when installation changes have occurred

[dirkleas]

instead of having the user keep track of when changes have been made (e.g. added, updated, or deleted plugins/modules), the system should be monitored and introspective JSON data generated automatically

perhaps something like tracking for changes on a a hash value in settings.json or similar based on something functionally similar to a shell command like ls -Rla $RACK_DIR/plugins | md5 -- maybe even use sha265 since that's what all the cool blockchain kids us ;-)