docs: github PR template

For issues like #11 and #8

.github/issue_template.md

@@ -0,0 +1,45 @@
+<!--
+
+Thanks for reporting a bug.
+
+If you fill out every section I can help.  If you don’t I’ll end up copy / pasting these questions again becausae I need them to help you.
+
+-->
+
+A specific example of an app that is broken: ...
+
+It is not broken in nixpkgs proper, because when I do:
+
+```
+$ nix build github:nixos/nixpkgs/nixpkgs-unstable#some-app
+$ echo $?
+0
+$ open result/Applications/Some.app
+```
+
+The app launches correctly.
+
+But when I install the app using `mac-app-util`, and do:
+
+```
+$ open ~/Applications/Home\ Manager\ Trampolines/Some.app
+```
+
+OR:
+
+```
+$ open /Applications/Nix\ Trampolines/Some.app
+```
+
+It crashes with error:
+
+```
+....
+```
+
+My system:
+
+```
+$ nix-info -m
+....
+```