Tag / Taxonomy management

[audi5]

This issue is to request documentation for how tag management works in Helix.
We understand through discussions with David that this already exists for the blogs project. This needs to be documented with FAQs answered in some place. If there's documentation already, can we please add that link to this ticket?

The acom team would like to leverage, test out the existing tag management capabilities to then call out the required enhancements.