HTTPResource and multiple Metadata Provider files

[Rod Widdowson]

> If you just happen to be curious enough and do find that there is some order preserved in loading multiple 
> MetadataProfider Chains, it would be good to know

Very much so, except that we make no guarantees about repetition inside a single source.

https://wiki.shibboleth.net/confluence/display/IDP30/MetadataConfiguration#MetadataConfiguration-SearchOrdering