Cannot freeze object with Buffer property

[alandotcom]

> freeze = require('deep-freeze-node')
[Function]
> freeze({foo: new Buffer(1)})
TypeError: Cannot prevent extension of an object with external array elements
    at Function.freeze (native)

[alandotcom]

You would want to change this line: https://github.com/AnatoliyGatt/deep-freeze-node/blob/8bc84206f68deaa8ce2aaccd59d114c8df0363ac/lib/deep-freeze.js#L27

> (new Buffer(1)) instanceof Object
true
> (new Buffer(1)).constructor === Object
false