+--- 1.6.21 2012/09/24
Rank tweak: follow=number will increase mult by number if two terms
occur next to each other; number-1 if they are one term apart , .. 0
--- 1.6.20 2012/09/21
-Rank algorithm details may be printed as part of show reseponse in
+Rank algorithm details may be printed as part of show response in
element <relevance_info>.. This is only printed if <rank debug="yes"/>
is used in service.