Decompress compressed string data

@param  {String} compressedData
@return {array<number>} decompressed data
function(compressedData) {
    var inflatedData =  zlib.inflateSync( new Buffer(compressedData, 'base64'));
    var outputString = "[" + String.fromCharCode.apply(null,inflatedData) + "]";
    var outputArray = JSON.parse(outputString);
    return ArrayConverter.diffsToValues(outputArray);
  }