doc: enhance Github templates.

- suppress the mini user guide.
- explain the 'traefik bug' command.

cmd/traefik/bug.go

@@ -17,11 +17,24 @@ import (
 var (
 	bugtracker  = "https://github.com/containous/traefik/issues/new"
 	bugTemplate = `<!--
-How to write a good issue?
+PLEASE READ THIS MESSAGE.
 
-Read https://github.com/containous/traefik/blob/master/.github/how-to-write-a-good-issue.md
+Please keep in mind that the GitHub issue tracker is not intended as a general support forum, but for reporting bugs and feature requests.
+
+For other type of questions, consider using one of:
+
+- the Traefik community Slack channel: https://traefik.herokuapp.com
+- StackOverflow: https://stackoverflow.com/questions/tagged/traefik
+
+HOW TO WRITE A GOOD ISSUE?
+
+- if it's possible use the command` + "`" + `traefik bug` + "`" + `. See https://www.youtube.com/watch?v=Lyz62L8m93I.
+- The title must be short and descriptive.
+- Explain the conditions which led you to write this issue: the context.
+- The context should lead to something, an idea or a problem that you’re facing.
+- Remain clear and concise.
+- Format your messages to help the reader focus on what matters and understand the structure of your message, use Markdown syntax https://help.github.com/articles/github-flavored-markdown
 
-And the contributing guide: https://github.com/containous/traefik/blob/master/.github/CONTRIBUTING.md
 -->
 
 ### Do you want to request a *feature* or report a *bug*?