Standardize config sample locations

All OpenStack projects store the full config sample in
etc/project_name/project_name.conf.sample, so we should do it in the same
manner.

Changes in etc/savanna:

* savanna.conf.sample -> savanna.conf.sample-basic
* savanna.conf.sample-full -> savanna.conf.sample

Additionally config sample was re-generated by config generator from
oslo that'll be added to Savanna in the next patch. Existing config
generation removed.

Change-Id: I7bfe1ab7cb32a9cdfe8f6b5ceead3dc97de74255
Merge "Standardize config sample locations"