Ability to easily prevent RBM FH assets from loading

[d4mation]

As mentioned in #70, the only way to prevent RBM FH assets from loading currently is by modifying the $wp_filter global, which is undesirable.

Disabling whether it loads or not could be useful. But there would be implications that would need to be considered: If multiple plugins are active that use RBM FH one shouldn't be able to prevent it from loading for another plugin on its CPT Edit screen, for example.