Add GH issue template (#272)

Author: jarrodmillman

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: true
+contact_links:
+  - name: Discussion forum
+    url: https://discuss.scientific-python.org
+    about: Please join the discussion!

.github/ISSUE_TEMPLATE/discuss.yml

@@ -0,0 +1,16 @@
+name: Create New Discourse Category
+description: Request a new category for our discourse forum (https://discuss.scientific-python.org/)
+labels: ["discourse"]
+
+body:
+  - type: markdown
+    attributes:
+      value: Thank you for your interest in our discussion forum.
+  - type: markdown
+    attributes:
+      value: Before continuing, you may want to review the difference between [categories and tags](https://blog.discourse.org/2017/10/its-time-we-talked-about-tags/).
+  - type: textarea
+    attributes:
+      label: Describe your issue.
+    validations:
+      required: true