Added automatic 'index.js' append to require() arugments that end in …

[Tythos]

…'/'; test and documentation added for this feature as a packaging shortcut; addresses feature proposed in Issue #1711

Note: CLA link now forwards from JQuery Foundation CLA (https://contribute.jquery.org/CLA/) to OpenJSF membership (https://openjsf.org/). Not sure what you want the new CLA-like agreement process to be? This may require a separate issue (meta-issue?) for project.

[Tythos]

Update on CLA comment: Signed from link in CI checks. May want to change link in page docs?

[Tythos]

CI failure appears to come from "const" usage within strict mode for chalk; not clear to me why this would be related to any commit changes. Other PRs appear to be bypassing, perhaps because they are on non-master branches from source fork for CI trigger? Unclear at this time.

[Tythos]

The CI build fails with identical results on <requirejs/requirejs> :master #898ff9e6.

> docker run -it node:0.12 bash
# git clone --depth=50 https://github.com/requirejs/requirejs.git requirejs/requirejs
# cd requirejs/requirejs
# npm install
# npm test

> requirejs@ pretest /requirejs/requirejs
> jscs . && jshint require.js

/requirejs/requirejs/node_modules/jscs/node_modules/cli-table/node_modules/chalk/index.js:2
const escapeStringRegexp = require('escape-string-regexp');
^^^^^
SyntaxError: Use of const in strict mode.
    at exports.runInThisContext (vm.js:73:16)