Go SDK: move preview package under preview subdirectory (#3571)

* Go SDK: move preview package under preview subdirectory

* move Go-specific config to readme.go.md

specification/cost-management/resource-manager/readme.go.md

@@ -0,0 +1,33 @@
+## Go
+
+These settings apply only when `--go` is specified on the command line.
+
+``` yaml $(go)
+go:
+  license-header: MICROSOFT_APACHE_NO_VERSION
+  namespace: costmanagement
+  clear-output-folder: true
+```
+
+### Go multi-api
+``` yaml $(go) && $(multiapi)
+batch:
+   - tag: package-2018-05
+   - tag: package-2018-09-preview
+```
+
+### Tag: package-2018-05 and go
+These settings apply only when `--tag=package-2018-05 --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-2018-05' && $(go)
+output-folder: $(go-sdk-folder)/services/$(namespace)/mgmt/2018-05-31/$(namespace)
+```
+
+### Tag: package-2018-09-preview and go
+These settings apply only when `--tag=package-2018-09-preview --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-2018-09-preview' && $(go)
+output-folder: $(go-sdk-folder)/services/preview/$(namespace)/mgmt/2018-09-01-preview/$(namespace)
+```

specification/cost-management/resource-manager/readme.md

@@ -106,41 +106,6 @@ python:
   output-folder: $(python-sdks-folder)/azure-mgmt-costmanagement
 ```
 
-## Go
-
-These settings apply only when `--go` is specified on the command line.
-
-``` yaml $(go)
-go:
-  license-header: MICROSOFT_APACHE_NO_VERSION
-  namespace: costmanagement
-  clear-output-folder: true
-```
-
-### Go multi-api
-``` yaml $(go) && $(multiapi)
-batch:
-   - tag: package-2018-05
-   - tag: package-2018-09-preview
-```
-
-### Tag: package-2018-05 and go
-These settings apply only when `--tag=package-2018-05 --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-2018-05' && $(go)
-output-folder: $(go-sdk-folder)/services/$(namespace)/mgmt/2018-05-31/$(namespace)
-```
-
-### Tag: package-2018-09-preview and go
-These settings apply only when `--tag=package-2018-09-preview --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-2018-09-preview' && $(go)
-output-folder: $(go-sdk-folder)/services/$(namespace)/mgmt/2018-09-01-preview/$(namespace)
-```
-
-
 ## Java
 
 These settings apply only when `--java` is specified on the command line.