PUBAPI-1169: .restdown BE GONE! index.restdown -> index.md
PUBAPI-1169: .restdown BE GONE! index.restdown -> index.md

arekinath/sdc-cloudapi,KrisShannon/sdc-cloudapi,joyent/sdc-cloudapi,joyent/sdc-cloudapi,KrisShannon/sdc-cloudapi,arekinath/sdc-cloudapi