Fixes a bug for `parse_param` plugin attribute being passed to tag generators (img)

Previously we set `parse_params="true"` behind the scenes which caused a bug for code that took all parameters such as the `<img>` tag generator. This will remove the auto setting attribute and simply keep the default behavior of parsing parameters by default. If a user wants to change it, they can add `parse_params="false"`.

This also has deprecation for the underscores in favor of `parse-params` instead.