;doc: update issue template, suggest checking manual

[ci skip]

.github/ISSUE_TEMPLATE/a-bug.md

@@ -9,13 +9,19 @@ Thank you for helping to make hledger better!
 If you're not sure it's a bug, or if some discussion would help,
 contact us first on the #hledger IRC chat room or the mail list:
 
-http://irc.hledger.org  (best; no chat client needed)
+- http://irc.hledger.org  (best; no chat client needed)
-http://list.hledger.org
+- http://list.hledger.org
 
-Some details that may be helpful to include: 
+Things to check before reporting:
+
+- Have you looked at (the right version of) the manual ? 
+  Use `hledger help [--help]` to view the built-in manuals,
+  or view the hledger.org -> REFERENCE MANUALS and choose the proper version at the top of the page.
+
+Details that may be useful to include when reporting: 
+
+- A minimal reproducible example  (--anon can help anonymise data)
+- Any related documentation you have found at http://hledger.org
+- The output of hledger --version
+- What platform you're on
 
-- a minimal reproducible example
-- what related documentation you found at http://hledger.org
-- your hledger version
-- how you installed it
-- what platform you're on.