Add shortkey browsing

u => next unread
p => new post
r => reply
c => cancel
a => previous post
z => next post
q => previous thread
s => next thread

Do not hesitate to change the shortkeys if you have better :p

git-svn-id: svn+ssh://murphy/home/svn/banana/trunk@138 9869982d-c50d-0410-be91-f2a2ec7c7c7b