replaced multiple calls to load config settings with LIMS:Local::Config->instance(), using Class::Singleton to ensure config file opened & read only once at server startup
moved HMRN data functions to new C::HMRN; fixed error in C::Test::print_pdf - now passes hashref (not string) to make_pdf(); new DB::PatientDemographic; new rule for capitalisation of $input in LIMS::Dispatch
