oops fix tabs space painfulness
fix formatting of jason array

arrays should have opening & closing square brackets, ie [], and also
require elements to be separated by commas.
http://www.json.org/

the up side of this is the node serialize output can be directly loaded
into python by cut and paste and forms a valid object (as would any well
formatted jason I guess, but this works for the node serialise now)
Merge pull request #7 from othane/node_serializer

Node serializer