Add missing files from 5.3

Author: fabpot

.github/ISSUE_TEMPLATE/3_Support_question.md

@@ -0,0 +1,11 @@
+---
+name: ⛔ Support Question
+about: See https://symfony.com/support for questions about using Symfony and its components
+
+---
+
+We use GitHub issues only to discuss about Symfony bugs and new features. For
+this kind of questions about using Symfony or third-party bundles, please use
+any of the support alternatives shown in https://symfony.com/support
+
+Thanks!

.github/ISSUE_TEMPLATE/4_Documentation_issue.md

@@ -0,0 +1,10 @@
+---
+name: ⛔ Documentation Issue
+about: See https://github.com/symfony/symfony-docs/issues for documentation issues
+
+---
+
+Symfony Documentation has its own dedicated repository. Please open your
+documentation-related issue at https://github.com/symfony/symfony-docs/issues
+
+Thanks!