add config class
update packaging infos
launch daemon with specific user
update requirements.txt
change logger level
fix pep8 warnings
add nginx conffiles in packaging
add contribs dir
fix unittests
launch bus in main thread
update default host in conffile
refactor config class
default username and password are still guest guest
remove the auto config instanciation from the config

When the config module was imported a configuration object was instanciated
making unitest unusable for a couple of reasons, including:
- no config file on my machine
- options passed to nosetests are forwarded to the config module leading to an error
  message saying that nose should be used with amid options
remove the branch from requirements.txt
Merge branch 'refactor_bus_interface'