string output bug in format.abc.Writer

[SmerkyG]

format.abc.Writer outputs the number of characters instead of the number of bytes when writing strings. This causes errors when outputting special characters. The following code fixes the problem:

class ABCWriter extends format.abc.Writer {
	override function writeString( s : String ) {		
		var encoding = null;
		#if neko
		var b = untyped new Bytes(s.length,s.__s);
		#else
		var b = Bytes.ofString(s, encoding);
		#end
		writeInt(b.length);
		o.writeFullBytes(b,0,b.length);
	}	
}

[ncannasse]

I think always using Bytes.ofString is the correct way, please submit a PR.