Add local install of Protractor E2E test suite

Modern best practices for NPM module installation have shifted away from
installing modules globally with -g, and instead installing them locally
(in the project directory) and checking them into your git repo. This is
a local install (with "npm install protractor") of Protractor v0.22.0.

One more step is needed before this will be useable: each developer will
need to run "node_modules/protractor/bin/webdriver-manager update" on
their respective development machines. This will download the WebDriver
drivers for each browser, which is a native application and will differ
by OS and so could not be checked into git.