Encode decode examples

[okdistribute]

This allows you to use the examples to encode a file and then decode it. I am assuming hex encoding but it could be encoded in other ways, right? What's the preferred encoding?

node example/encode.js example/alexandria.pbf > encoded.peermaps
node example/decode encoded.peermaps

Another question: does decoded work fine like this line by line, or do they need to be decoded in batches?