Expose the `Context` in `HelperContext`

[nwoolls]

I'd like to create a tag helper that outputs all of the tag names and values. Something useful to consumers of my project so they can easily see all of the tags (names and values) passed into a template, and then customize the template themselves.

Something like {{tags}} that would output the dictionary in JSON format.

I didn't see any official support for this (I tried e.g. {{#.}}{{.}}{{/.}} without luck) and stumbled on this library which looked promising. However, the HelperContext does not provide access to the Context (which is private) or underlying view data. So I don't seem to be able to do this.

Thoughts? Suggestions? Thanks!