message: Add new api version of reservation for go SDK
diff: @@ -13,11 +13,21 @@ go:
  ``` yaml $(go) && $(multiapi)
  batch:
  + - tag: package-preview-2019-07-19
  - tag: package-preview-2019-04
  - tag: package-2018-06
  - tag: package-2017-11
  ```
  +### Tag: package-preview-2019-07-19 and go
  +
  +These settings apply only when `--tag=package-preview-2019-07-19 --go` is specified on the command line.
  +Please also specify `--go-sdk-folder=<path to the root directory of your azure-sdk-for-go clone>`.
  +
  +``` yaml $(tag)=='package-preview-2019-07-19' && $(go)
  +output-folder: $(go-sdk-folder)/services/preview/$(namespace)/mgmt/2019-07-19-preview/$(namespace)
  +```
  +
  ### Tag: package-preview-2019-04 and go
  These settings apply only when `--tag=package-preview-2019-04 --go` is specified on the command line.
  