Pages with no CSS cause an error in the WARC creation process

[machawk1]

This is due to a naive loop ~354 in warcGenerator.js

    for(var cc=0; cc<cssURIs.length; cc++){
            if(requestHeader == cssURIs[cc]){
                respContent += cssData[cssURIs.indexOf(requestHeader)] + CRLF + CRLF;
                break;
            }
        }