New spice inputs for New.pm

New spice inputs for description, source domain, and template group. Option to create a relevancy block.

Connected changes in the spice repo - https://github.com/duckduckgo/zeroclickinfo-spice/pull/1034
After testing this out I realized `$lia_name` is no longer what we need to use inside our spice templates. We need to take the given name from CamelCase and convert it to snake_case and use that within the JS templates. There is a "camelToUnderscore" function in duckpan.pm which you can borrow to achieve the conversion