added arista models

models/arista

models/tapi/ietf-yang-types.yang

models/tapi/tapi-common@2019-03-31.yang

models/tapi/tapi-connectivity@2019-03-31.yang

models/tapi/tapi-dsr@2019-03-31.yang

models/tapi/tapi-equipment@2019-03-31.yang

models/tapi/tapi-eth@2019-03-31.yang

models/tapi/tapi-notification@2019-03-31.yang

models/tapi/tapi-oam@2019-03-31.yang

models/tapi/tapi-odu@2019-03-31.yang

models/tapi/tapi-path-computation@2019-03-31.yang

models/tapi/tapi-photonic-media@2019-03-31.yang

models/tapi/tapi-streaming@2017-11-13.yang

models/tapi/tapi-topology@2019-03-31.yang

models/tapi/tapi-virtual-network@2019-03-31.yang

models/tapi/yuma-ncx.yang