Using overlapping fields in a `struct` to achieve C `union`-like functionality is not documented well enough about emboss

[reventlov]

Use:

struct Foo:
  0 [+1] UInt:8 a
  0 [+2] UInt:16 b

There is no union keyword because you can already specify overlapping fields in any struct (or bits).

This feature is mentioned in the User Guide (though only briefly), but not, as far as I can see, in the Language Reference. It would also probably be worth having a FAQ page or a "Recipe Book", and answering this question there.

[fsareshwala]

That makes sense. I thought about this approach after making this pull request but I wasn't sure if this is the way it's supposed to be done. Good to know that it is.

I put in a pull request (#102) to address the documentation issue for now.