Update MythWeb README

[sphery <mtdean@…>]

Trivial patch to update the MythWeb README.

• Removes references to the php_sessions directory (as it's no longer required with the session information stored in the database).
• Includes instructions for submitting patches to Trac.

Note that I did not update the version number (still 0.17), date (still February 6, 2005), or the "future tense" part of the "About" description (I'd say that MythWeb has already met the goals stated in the first sentance).

Yes, I know nobody actually reads the README until you tell them to read it after they've asked an FAQ on the list, but here's an update, anyway. ;)

[sphery <mtdean@…>]

Updated to remove changes already committed in r7673

[xris]

(In [7696]) apply patch to close #332