Refactor getArray/getOptionalArray

lib/SimpleSAML/Auth/ProcessingChain.php

lib/SimpleSAML/Configuration.php

lib/SimpleSAML/Database.php

lib/SimpleSAML/Metadata/MetaDataStorageHandler.php

lib/SimpleSAML/Metadata/MetaDataStorageHandlerSerialize.php

lib/SimpleSAML/Metadata/SAMLBuilder.php

lib/SimpleSAML/Module.php

lib/SimpleSAML/Stats.php

lib/SimpleSAML/Store/SQLStore.php

lib/SimpleSAML/Utils/XML.php

modules/multiauth/lib/Auth/Source/MultiAuth.php

modules/saml/lib/Auth/Source/SP.php

modules/saml/lib/IdP/SAML2.php

modules/saml/lib/Message.php

tests/lib/SimpleSAML/ConfigurationTest.php