network:Separate the translatable messages into different catalogs

oslo.i18n uses different marker functions to separate the
translatable messages into different catalogs, which the translation
teams can prioritize translating.  For details, please refer to:
http://docs.openstack.org/developer/oslo.i18n/guidelines.html#guidelines-for-use-in-openstack

There were not marker fuctions some places in directory network.
This commit makes changes:
* Add missing marker functions
* Use ',' instead of '%' while adding variables to log messages

Change-Id: Id19436f4226bb60baef65974a62641095e334b1f
Merge "network:Separate the translatable messages into different catalogs"