Try to make our PGP signing more useful:

Try to make our PGP signing more useful:

 * All the PuTTY tools for Windows and Unix now contain the fingerprints of
   the Master Keys. The method for accessing them is crude but universal:
   a new "-pgpfp" command-line option. (Except Unix PuTTYgen, which takes
   "--pgpfp" just to be awkward.)

 * Move the key policy discussion from putty-website/keys.html to
   putty/doc/pgpkeys.but, and autogenerate the former from the latter.
   Also tweak the text somewhat and include the fingerprints of the
   Master Keys themselves.
   (I've merged the existing autogeneration scripts into a single new
   one; I've left the old scripts and keys.html around until such time
   as the webmonster reviews the changes and plumbs in the new script;
   he should remove the old files then.)

[originally from svn r5524]
[this svn revision also touched putty-website]