Miscellaneous Version Changes

We are now in 1.0.3, so I've updated this in some places, will do a sweeping change for the rest upon confirmation

Felt that LRS MUST accept may leave some cases that an LRS MUST NOT reject was clearer about (picky, I know, but seemed more accurate)

We can't enforce a description will be meaningful, so I changed that part to a SHOULD

Header language wasn't disambiguating name from value, so I added the value to the corresponding tag

Finally, I don't think we care too much if systems convert between the 1.0.Xs, what we care about are breaking changes i.e. minor and major versions.
Yeah, I'm not sure how I feel about this... I'm also not sure what "converting statements" means in practice. I think as the IEEE effort decomplects the data model from the bindings this might become easier to reason about; there shouldn't be a technical reason (beyond poor implementation) that version headers can't be used to return the Statement in the requested format, beyond breaking changes (major versions). 

I like the sentiment, but I think it requires more thought.