Add nodejs chaincode support

[jt-nti]

As a nodejs developer, I want to use the starter kit to build chaincode written in the language I'm already familiar with

[erin-hughes]

Things we need to do:

• [x] Put something in the bootstrap repo, including tests :)

• [x] Add a button to the toolchain readme with the new nodejs bootstrap repo

• [x] Add tests for the nodejs build stuff

• [x] Update the build-lib test script to run tests in the bootstrap repo

[jt-nti]

Think this is all done!! Thank you!