Schema

This installs the 'schema' folder into _attachments, which includes the schema for versions 1.01 and 2.01. It also adds an example python script to run validation of data for a schema (using the python module jsonschema). 

The next step would be to implement this schema validation in the index.js. For this to happen, we will probably want to install the minimal set of libs from the JSV project (https://github.com/garycourt/JSV) to perform this validation. This shouldn't take much effort to implement - there is already an example in the repo and multiple examples can be found with a google search.