Curry reloadContainerOnClick for more flexibility

Allow multivariate configuration options as well as multivariate
selectors. Add an option for a callback to be sent to the $.load
function on completion.
Don't iterate paginator over whole collection

This is necessary in order to add more steps to be run for each
`_get_row_data` query. These queries will be expensive, better to run 10
than 500.
Make importer api call wrappers more DRY
PR Fixup: Use more performant paginator count fn
PR Fixup: Use simpler $().load callback hook