DIAGONAL PRESENT not detected when FORMAT line is split into multiple tokens

In .dl files where FORMAT = FULLMATRIX DIAGONAL PRESENT is split across multiple tokens (e.g., FULLMATRIX, DIAGONAL, PRESENT appearing as separate list elements), the readDLKeywords() function fails to recognize the DIAGONAL keyword. As a result, valid self-loops are not created during parsing. Parser should be updated to handle these standalone tokens outside of FORMAT=... expressions.