code: public static Observable<String> byLine(Observable<String> source) {
          return split(source, ByLinePatternHolder.BY_LINE);
      }
docs: Splits the {@link Observable} of Strings by line ending characters in a platform independent way. It is equivalent to
  <pre>split(src, "(\\r\\n)|\\n|\\r|\\u0085|\\u2028|\\u2029")</pre>
  <p>
  <img width="640" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/St.byLine.png" alt="">
  
  @param source
  @return the Observable conaining the split lines of the source
  @see StringObservable#split(Observable, Pattern)