Abstract out a smart component for configuration-record maintenance

Lots of settings pages have very similar code: e.g. ui-organization/settings/Locale.js and ui-organization/settings/Bindings.js have the same manifest that knows how to talk to mod-configuration, the same proptypes that declare the relevant resources and mutators, the same save function that uses either POST or PUT depending on whether the record already exists, etc.

We should abstract out this functionality into a smart component that does 90% of the work, so that the individual settings pages become simple invocations of that component with a couple of callback functions.

(Once we have this, it will become easier to add UI functionality for handling both user-specific and global preferences – see the umbrella issue STCOR-111.)