Do not load refinery admin javascripts again.

Refinery itself takes care of loading the admin javascripts including pagination.

Including this line results in it being included twice -- once by this manifest and once by refinerycms-core's refinery/application manifest.

Note that this change must be used in conjunction with moving the visual_editor_javascripts block on refinerycms-core to *after* the refinery/application include tag. This will be sent in a pull request i'm about to raise once Github lets me push to my refinerycms repo. I'll edit in here once it is.