updated the issues list /tracking TBD ones

Shivaram,

I've just updated the issues list. The only that is not closed is mine ;-)

I tried to track the ones that say TBD in the spec's changelog, but
I'm unable to find them in my mailbox. Could you send me their URL or
forward their message so that I can track them? 

Should we add an issue for stringprep or leave it just in the changelog?

-jose