Added John Maddock to list.

[SVN r21372]

more/blanket-permission.txt

@@ -8,3 +8,5 @@ Daniel Frey (d.frey -at- gmx.de, daniel.frey -at- aixigo.de)
 Douglas Gregor (greod@cs.rpi.edu)
 Aleksey Gurtovoy (agurtovoy@meta-comm.com)
 Dave Moore (dmoore -at- viefinancial.com) (See Boost list message of 18 Dec 2003 15:35:50 -0500)
+John Maddock (john - at - johnmaddock.co.uk)
+