ABI stable module ports

[mhdawson]

We are working on a number of ports of modules to the ABI Stable PoC. This issues is to provide links to to those ports:

Module	Status	Link	Branch
node-sqlite3	Work in progress	https://github.com/mhdawson/node-sqlite3/tree/v3.1.4-abi	v3.1.4-abi
node-nanomsg	Done	https://github.com/sampsongao/node-nanomsg/tree/api-opaque-prototype	api-opaque-prototype
leveldown	Done	https://github.com/boingoing/leveldown/tree/api-opaque-prototype	api-opaque-prototype

[aruneshchandra]

Going forward - we will track this info on the main readme page.