Node.js SDK - custom API versioning

• allows for targeting a specific API version, by setting WIT_API_VERSION

Node.js SDK - API versioning + warns when validating actions

• adding API versioning (defaults to 20160516)
• warns instead of throwing when validating actions
• fixing null values when cloning context

Node.js SDK - node-fetch, message context, sync callbacks

• callbacks are not called asynchronously by default, choice is left to the developer (use process.nextTick in your callback to emulate the previous behavior)
• using node-fetch instead of requests
• the message() API takes now an optional context as second parameter

Node.js SDK - fixes

• fixing context not updated in interactive mode
• fixing array values in context
• create readline interface only in interactive mode

Node.js SDK - unifying action parameters

Breaking changes:

• the say action now takes 4 parameters: sessionId, context, message, cb
• the error action now takes 3 parameters: sessionId, context, error

Node.js SDK - new action parameters

Breaking changes:

• the merge action now takes 5 parameters: sessionId, context, entities, message, cb
• the error action now takes the context as second parameter
• custom actions now take 3 parameters: sessionId, context, cb