Add a note to attach the logs as a file rather than text.

Signed-off-by: Kilian von Pflugk <github@jumoog.io>

.github/ISSUE_TEMPLATE/bug_report.md

@@ -24,6 +24,9 @@ A clear and concise description of what you expected to happen.
 **Screenshots**
 If applicable, add screenshots to help explain your problem.
 
+**Log files**
+Please try to attach log files rather than pasting the log contents. It makes the issues easier to read.
+
 ** Environment (please complete the following information):**
  - OS: [e.g. Linux]
  - Version [e.g. 22]