Samples are supposed to show good practices and in most cases we don't use the time scale but require `Chart.bundle.js`, which is not correct. Instead, we should require the non-bundled version in its minified version (`Chart.min.js`). Paradoxically, time based examples don't use `Chart.bundle.js` but require moment manually side to `Chart.min.js`, which IMO is also the correct way since it allows users to configure and use moment globally (TZ, locales, etc.) and doesn't enforce a specific moment version.
Also remove the `data-labelling.html` example because we now have an [official plugin](https://github.com/chartjs/chartjs-plugin-datalabels) that implements this feature and don't want to deal with user custom code anymore.
Account for zero indexing of arrays when creating a name for an added dataset and remove the last dataset in the array when removing a dataset rather than removing the first.
Inject the GA tracking snippet for all samples, including the index page. Also update README.md badges using the shields.io service for consistency with flat-square style and cache, and add release badges to the installation documentation page.
* Adds step-after functionality, true defaults to step-before
* Update stepped line sample to include all variations of steppedLine configurations
* Update documentation on steppedLine values
* Add tests for new steppedLine values 'before' and 'after'
