Added LCMPT and AFSET sub-vocabularies to LOC

Added LCMPT and AFSET sub-vocabularies to the
Library of Congress vocabulary. In addition,
fixed a slight name misspelling on the README.
Merge pull request #60 from scande3/add_lcmpt_afset

Added LCMPT and AFSET sub-vocabularies to LOC
Updating route syntax

In order to distinguish between an individual authority and an
individual sub-authority, it must be declared in the url.
Removing deprecated ::get_full_record
Refactor local authorities; implement #all method