Fix some items in schema
Fix some items in schema

- comment on admin.key was about riak-cs, shoule be about stanchion
- platform_bin_dir comment "(substituted by rebar)" in not needed
- log.syslog.facility s/Riak/Stanchion/
- zdbbl "override zdbbl from 1mb to 32mb" is not needed
- leveldb.limited_developer_mem is not needed

basho/stanchion,sdebnath/stanchion