Use the deployment pattern to load ES5 and/or ES6 shims

[unscriptable]

At first it seems kinda strange, but it makes a lot of sense to use the deployment patterns to load shims. When using a boot.js-replacement deployment pattern, the initial script to load is boot.js. When using a <script>-replacement pattern, you would expect a previous <script> to inject shims.

Our default shim could be a browserified (or crammed) poly.js. (Via rave extension, people could decide to use the es5-shim or es6-shim projects, instead.)

One thought about using poly.js is that we could create two versions: an ES5 shim and an ES6 shim. The test to decide whether to load the ES5 shim is to test for an "early" ES6 feature such as Array.isArray or Object.observe. The reason this might work is because (afaik) all the browsers that support those features already support 100% of the ES5 features.

For the foreseeable future, we should always load the ES6 shim.

[unscriptable]

My current thinking is that we should not make efforts to support non-ES5 browsers. Devs can add es5 polyfills in various ways. As regards ES6 polyfills, if we don't use ES6 features (besides Promises which come for free), then we don't have to worry about shimming.

If devs want to use es6 features in their app code, that's cool. They should install a set of polyfills.