Bug in ResourceFinder.js

[angeldavid-monteagudo]

Hi,

I think I found a bug in https://github.com/xiaoyuze88/isomorphic-pkg-reader/blob/master/lib/ResourceFinder.js when dealing with resource references (around line 347).

In line 358 this.putIntoMap("@" + idStr, data); is called even though data is not set when value_dataType == TYPE_REFERENCE. This results in an extra null every two positions of the resulting array. Moreover, in line 384, for (var value in values) is used to iterate on an array. This should probably be for (var value of values), right now the resulting array is filled with zeros instead of the value at position zero.

I'm afraid I don't have time for a pull request at this moment, sorry about that.