Switched from self-made config to oslo.config

Something is already working, but it needs further testing and refactoring
Memo:
fix failing test
fix pep8 errors
think what to do with copyright in tools/conf/* files copied from nova
rename 'host' and 'port' to 'listen_address' and 'listen_port'
rephrase help strings for config options; right now they are pretty ugly
oslo-config has been upgraded to the latest version
Merge remote-tracking branch 'origin/oslo_config' into dev
oslo context has been added
Merge branch 'dev' into oslo_config
some cleanups, tests fixed
unused option dev removed;
analyze_opts.py removed;
eho.conf.sample updated
Merge pull request #11 from Mirantis/oslo_config

Switched from self-made config to oslo.config
refactoring: eho.server -> eho
unused configs has been removed
Merge branch 'oslo_config' into dev
tests runner has been fixed
stollen files has been moved to openstack package
get_auth_token has been fixed
conf-print has been removed
plain py logging replaced with oslo log
logging of defaults generator has been cleaned
sample confs has been improved
oslo upgraded
unused arg has been removed