Add welcome message to point users at Go modules

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Author: alexellis

template/golang-http-armhf/template.yml

@@ -1,2 +1,12 @@
 language: golang-http
 fprocess: ./handler
+welcome_message: |
+  You have created a new function which uses Golang 1.13.
+
+  To include third-party dependencies, use Go modules and use
+  "--build-arg GO111MODULE=on" with faas-cli build or configure this  
+  via your stack.yml file.
+
+  See more: https://docs.openfaas.com/cli/templates/
+  For detailed examples:
+  https://github.com/openfaas-incubator/golang-http-template

template/golang-http/template.yml

@@ -1,2 +1,12 @@
 language: golang-http
 fprocess: ./handler
+welcome_message: |
+  You have created a new function which uses Golang 1.13.
+
+  To include third-party dependencies, use Go modules and use
+  "--build-arg GO111MODULE=on" with faas-cli build or configure this  
+  via your stack.yml file.
+
+  See more: https://docs.openfaas.com/cli/templates/
+  For detailed examples:
+  https://github.com/openfaas-incubator/golang-http-template

template/golang-middleware-armhf/template.yml

@@ -1,2 +1,12 @@
 language: golang-middleware-armhf
 fprocess: ./handler
+welcome_message: |
+  You have created a new function which uses Golang 1.13.
+
+  To include third-party dependencies, use Go modules and use
+  "--build-arg GO111MODULE=on" with faas-cli build or configure this  
+  via your stack.yml file.
+
+  See more: https://docs.openfaas.com/cli/templates/
+  For detailed examples:
+  https://github.com/openfaas-incubator/golang-http-template

template/golang-middleware/template.yml

@@ -1,2 +1,12 @@
 language: golang-middleware
 fprocess: ./handler
+welcome_message: |
+  You have created a new function which uses Golang 1.13.
+
+  To include third-party dependencies, use Go modules and use
+  "--build-arg GO111MODULE=on" with faas-cli build or configure this  
+  via your stack.yml file.
+
+  See more: https://docs.openfaas.com/cli/templates/
+  For detailed examples:
+  https://github.com/openfaas-incubator/golang-http-template