Document process for sorting a node view by taxonomy term (various edge cases)

@iamjon: One solution I used was this one (linked above), but the fact that I opened this issue several months later suggests it wasn't a fix for all situations. If I recall which view I was working on I'll update the ticket.

I think we might need to write up various use cases and solutions here, because sort actually works in the most basic usage, it's just "everything else" which doesn't always work out of the box. IMO what's catching people is not the basic functionality, but secondary requirements which need consideration for each case (" ... where the node has terms in multiple vocabularies", " ... where the taxonomy term weight does not match alphabetical sort", " ... where P != P").

Some edge cases; please expand if you think this is a good approach -

• Node has terms in vocabs A,B,C; want to sort by terms from vocab B only. By default "sort by taxonomy term" will produce alphabetical sort from all vocabs. Solution is to add a filter requiring results to have a term in vocab B
• Taxonomy terms are not weighted alphabetically. By default Views will return sort by {term_data}.name not {term_data}.weight (?). Perhaps use computed_field module here.
• ...