debuglogging is too chatty, needs flags

[Mrten]

As stated in my previous issue #222, logging is way too chatty by default. There is the severitylevels but INFO is too silent... What would help tremendously is that one could toggle the different submodules, like exim does (mail server):

http://www.exim.org/exim-html-current/doc/html/spec_html/ch-the_exim_command_line.html#SECID39

take a look at '-d'. I'm sorry for not having a better link...