SP settings shouldn't need local path to IDP Metadata

[bjm88]

Right now the settings config and init require a local path to the file of the IDP meta data. This is not desirable since many multi tenant programs would load this config dynamically from db or have it injected in test, or even just point at the live URL from IDP to get meta data each time. As the library stands today must download this xml, save it locally (in cloud serverless env its not ideal to rely on saving to local file system) to the get file path to just pass to this library....