audit and clean code

Reading through the code I found a number of things that jumped out at
me.

* markup dead code (will remove after further confirmation)
* remove several dead comments, dead code, etc
* tweak commit and profile creation behavior

Profile behavior is now more consistent.
When setting up a profile, we prefer certain keys in certain order,
and this makes things flexible and expressive for the user.

The user profile's author key in particular is favored above all other
pieces of information.  This key is set by result from
server.fetchUser, which can be modified by subscribing to
server.events.on('profile', function (hook, next)), or by supplying
`opts.fetchUser(name, fn)` to `createServer`.
remove dead code
update readme with profile creation demo