Update CONTRIBUTING.md

CONTRIBUTING.md

 # Contributing
 
-If you have any issues or ideas for improvement you can contact me in the [CMK forum](https://forum.checkmk.com/) by sending me a direct 
-message to `@thl-cmk` (this is the prefered way) or send me an email to _thl-cmk[at]outlook[dot]com_.
+If you have any issues or ideas for improvement you can contact me in the [CMK forum](https://forum.checkmk.com/) by sending me a direct message to `@thl-cmk` (this is the prefered way) or send an email to _thl-cmk[at]outlook[dot]com_.
 
-If you have any issues at least let me know what CMK version/edition you are running, what Fritzbox (model/version) you are using.
+Please include:
+- your CMK version/edition
+- your environment (stand alone or distributed)
+- the OS of your CMK server(s)
+- the version of the plugin
+- the crash report (if any)
 
-For some fixes/improvements I migth need the _agent output_ from the device in question.
-
-For example, first get the actual command line from CMK:
+For agent based plugins I might need also the agent output of the plugin.
 ```
 OMD[build]:~$ cmk -D ares | grep Program
   Program: /omd/sites/build/share/check_mk/agents/special/agent_fritzbox 192.168.10.254