Add a Tag Type property to Tags

I think it would be useful for clients to know what **category** of thing a given tag represents - for example _Programming Language_ (C#, C, C++, F#, Rust etc), _Stream Language_ (English, German, etc) and _Framework_ (.Net Core, Vue.js, etc). A new column should be added to the Tags table for this, along with a supporting table of TagCategories. Then the Admin pages should be updated to allow administrators to categorize tags. The tag category should be mandatory.

This would allow clients to display tag choices grouped by type, like this:

(example above using Adaptive Cards)

Other categorizations might be useful, but these 3 should be supported at minimum, along with **Other** to account for tags where its not obvious which category the tag falls into..