SCDL single-source profile (fixes #7647)

This creates a single, combine provider for SCDL hosted by
College of Charleston, which replaces the three existing
SCDL sources (Clemson, Charleston, and USC).

Additional changes:

* Improve SCDL-specific geographic enrichments to identify
state as South Carolina and country of United States when
possible
* Add `dcterms:hasFormat` to the OAI module.
* Remove deleted cleanup_language module from test setup
Merge pull request #30 from dpla/7647-scdl

SCDL: new profile for single feed provided by College of Charleston