improve issue template

Author: cowtowncoder

.github/ISSUE_TEMPLATE.md

@@ -1,6 +1,7 @@
 We appreciate issues as very valuable contributions, but just to make sure here are things that are important to do before filing an issue:
 
-* Only report issues, and ask Usage Questions on [Jackson-users](https://groups.google.com/forum/#!search/jackson-users) list -- you are more likely to get help that way
+* Only report issues (and perhaps request new features, FEATURE):,Usage Questions should be asked on [Jackson-users](https://groups.google.com/forum/#!search/jackson-users) list -- you are more likely to get help that way (and we will promptly close questions-as-issues)
 * Check to see if this issue has already been reported (quick glance at existing issues): no deep search necessary, just quick sanity check
 * Include version information for Jackson version you use
 * (optional but highly recommended) Verify that the problem occurs with the latest patch of same minor version; and even better, if possible, try using the latest stable patch version
+    * For example: if you observe an issue with version `2.4.1`, first upgrade to `2.4.6` to ensure problem has not already been fixed.