Need test run command in Getting Started

[bdharris08]

https://mochajs.org/#getting-started

Problem: getting started has you install mocha locally, make a test dir, and write a test, but doesn't show you how to run it nor how to set up npm test.

Suggestion: instruct users to add a test script to package.json such as:
If mocha is installed locally:
"scripts": { "test": "./node_modules/mocha/bin/mocha" },
If mocha is installed globally:
"scripts": { "test": "mocha" },
And then run it with $ npm test

Expected: some instruction on how to run tests after installing mocha.
Current:

[ScottFreeCode]

See also mochajs/mocha#2282 (comment)