Add subcollections

• Incoming records can be grouped into subcollections based on whether specified fields match the subcollection's pattern.
• Subcollections can have id affix's that are added to the institution/workflow/collection affix chain
• Incoming files are allowed to have duplicate ids when records are in separate subcollections
• Subcollections can define parameters (e.g. "provider_param: SPIE"). Specs adding fields can reference those parameters (e.g. "value: 'Content provider: provider_param.'). Fields are created for each record using the paramter values of the record's subcollection.