add an issue template

.github/Issue-template.md

@@ -0,0 +1,28 @@
+
+#### Do you want to request a *feature* or report a *bug*?
+
+<!-- 
+If you have a question, you might ask it in our Slack channel instead.
+
+https://slate-slack.herokuapp.com/
+-->
+
+#### What's the current behavior?
+
+<!-- 
+For bugs, please create a JSFiddle that reproduces the issue using 
+our template, and include a GIF showing how to easily reproduce it.
+
+https://jsfiddle.net/2zokvrvt/7/
+http://recordit.co/
+-->
+
+#### What's the expected behavior?
+
+<!-- 
+Researching how other editors handle this issue is super helpful!
+
+https://draftjs.org/
+http://prosemirror.net/
+https://quilljs.com/
+-->