Update issue/PR templates, contributing.rst, CI

- Keep documentation in sync with master branch

- Run PyLint and MyPy on Github Actions

- Update Issue templates, enforce usage of issue templates, add links to
  resources in Instaloader Documentation

- Update contributing.rst

.github/workflows/windows_exe.yml

@@ -4,6 +4,7 @@ on: [push, pull_request]
 
 jobs:
   build:
+    name: Windows EXE build
     runs-on: windows-latest
     steps:
       - name: Checkout Instaloader repository