message: update handlebars to support Rust 1.23.0
diff: @@ -27,7 +27,7 @@ serde_json = "1.0"
  serde_derive = "1.0.75"
  atty = "0.2.5"
  clap = "2.29"
  -handlebars = { version="1.0.2", optional = true }
  +handlebars = { version="1.0.3", optional = true }
  csv = "1.0"
  walkdir = "2.2.3"
  