Make information about the client available in the `connection` object.
Update client info API to just have `connection.clientAddress` and `connection.httpHeaders`.

Fix documentation.

Expose webapp's `identifyBrowser`, even though we aren't currently
using outside of webapp.
Move block for computing httpForwardedCount from the top of the file into where it is used.

This is less efficient, as we don't actually need to compute it every time.
However, I think this is pretty small compared to the other work we're doing
(string splitting via regexp, string copies, etc).

This makes the code clearer and easier to understand, as all the code is in
one place. Also, it was distracting at the top of the file as it came before
the commit saying what was in the file.
History.md entry
Merge branch 'pr-1783' into devel