Convert hashtags to tag option - exists, but doesn't seem to work, and isn't documented

I’m not seeing an issue here with importing a file or even adding hashtags to a Markdown document and having them detected automatically.

However, @cgrunenberg would have to comment on…

  1. I don’t believe the Tags should be detected in MultiMarkdown metadata, e.g., the second line…
  2. The detected tags are now preserving the # and previously didn’t. I don’t think they should.