[security-services] Draft-sstc-sec-consider-03.doc

Here's the latest, incorporating the following:

1) Eve's changes
2) My changes in response to Eve's comments
3) Comments and changes from Prateek
4) Filling in my TBDs
5) Added a section on Key Management (background on the limitations of
security based on key-to-identity binding strength)
6) Added a Privacy section. This is basically a comment that you should
keep private things confidential combined with a section on anonymity
that is based pretty heavily on Marlena's notes to the list.

I am looking forward to comments and additional text from everyone, as
they review the document. 

C.