Renamed DBIx::Class::PK's retrieve() as find()

Renamed DBIx::Class::PK's retrieve() as find()
Renamed DBIx::Class::Table's retrieve_from_sql() as search_literal()
Renamed DBIx::Class::Table's count_from_sql() as count_literal()
Removed DBIx::Class::Table->retrieve_all()
Added DBIx::Class::CDBICompat::Retrieve to account for method renaming
Updated affected test cases