v0.16.1

Full Changelog: v0.16.0...v0.16.1

"Only" change is the bump to the minimal required version - 1.23.13 - of aws-sdk-go to support WebIdentityRoleProvider

Build with

docker run -v $(pwd):/go/src/github.com/kelseyhightower/confd -w /go/src/github.com/kelseyhightower/confd golang:1.10.8 bash -c 'curl -s https://raw.githubusercontent.com/golang/dep/master/install.sh | sh; dep ensure; make'