pua_dialoginfo: load dialogs for dialoginfo event upon restart

- based on a patch by Kristian Høgh, FS#360
pua_dialoginfo: store pubruri for caller and callee in dlg vars

- to be restored upon restart
- based on a patch by Kristian Høgh, FS#360
pua_dialoginfo: indentation and better fit in 80chars line
pua_dialoginfo: documentation for new parameters

- pubruri_caller_dlg_var and pubruri_callee_dlg_var
pua_dialoginfo: README regenerated