Add support for dynamic 'url' on remote validator, also adds support for setting type: POST/GET

Addresses issues [#391](https://github.com/nghuuphuoc/bootstrapvalidator/issues/391) and [#392](https://github.com/nghuuphuoc/bootstrapvalidator/issues/392)

Post type defaults to POST.

Dynamic url follows same format as dynamic data function.

Signed-off-by: Eric Nakagawa @ericnakagawa