[REF] Use events for CMS resource loading

[colemanw]

Overview

Refactors the way hook_civicrm_coreResourceList is called internally to use the new eventDispatcher system.

Before

Function called in ad-hoc fashion.

After

Function called using standard event dispatcher.

[civibot]

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[totten]

Oh, snap. Loose coupling.

r-code generally looks good/consistent. Re: r-run, checked on WP+D7.