.github: update template engine, fix issue template random linking to PR

.github/ISSUE_TEMPLATE.md

@@ -1,23 +0,0 @@
-#### Issue details
-_Please describe the problem, or desired feature_
-
-#### Version
-_What version was the issue encountered with_
-
-#### Platform
-[  ] All
-[  ] AntennaTracker
-[  ] Copter
-[  ] Plane
-[  ] Rover
-[  ] Submarine
-
-#### Airframe type
-_What type of airframe (flying wing, glider, hex, Y6, octa etc)_
-
-#### Hardware type
-_What autopilot hardware was used? (pixhawk, pixracer, PX4FMU etc)_
-
-#### Logs
-_Please provide a link to any relevant logs that show the issue_
-

.github/ISSUE_TEMPLATE/bug_report.md

@@ -9,7 +9,7 @@ Questions and user problems should be directed at the forum (http://discuss.ardu
 _**Please be very sure you have found a bug when opening this issue**_
 If there was a previous discussion in the forum, link to it
 
-### Bug report
+## Bug report
 
 **Issue details**
 

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: User Support and General Questions
+    url: https://discuss.ardupilot.org/
+    about: Please ask on https://discuss.ardupilot.org/

.github/ISSUE_TEMPLATE/feature_request.md

@@ -9,7 +9,7 @@ Questions and user problems should be directed at the forum (http://discuss.ardu
 _**Please do a careful search before opening this, there are already a lot of feature requests**_
 If there was a previous discussion in the forum, link to it
 
-### Feature request
+## Feature request
 
 **Is your feature request related to a problem? Please describe.**
 _A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]_