BEM-block path detection to pinpoint modules

[joshiefishbein]

Add optional flag for BEM block detection on violations.

When a violation is found, the tree will be crawled for BEM block classes to help pinpoint problematic components.

Example:
If a the following node was reported problematic because it didn't have a label:

<button class="Button">
	<img class="Image" src="./next-arrow.png" />
</button>

We could identify the exact button in the DOM and create a list of parents with BEM base block classes.

.ArticleView > .ArticleHeader > .TopBar > .ArticlePagination > .Button > .Image