Use new name for cat19

This cannot be merged until JRuby has released a version that
supports it, and should not be released until we have decided how
to transition away from older JRuby versions that do not have this
name.

See ruby#83

ext/java/org/jruby/ext/stringio/StringIO.java

@@ -1299,7 +1299,7 @@ private long stringIOWrite(ThreadContext context, Ruby runtime, IRubyObject arg)
                 if (enc == EncodingUtils.ascii8bitEncoding(runtime) || encStr == EncodingUtils.ascii8bitEncoding(runtime)) {
                     EncodingUtils.encStrBufCat(runtime, ptr.string, strByteList, enc);
                 } else {
-                    ptr.string.cat19(str);
+                    ptr.string.catWithCodeRange(str);
                 }
             } else {
                 strioExtend(ptr.pos, len);