Add justfile

justfile

+# Just file: https://github.com/casey/just
+
+test:
+    pytest
+
+release version: test
+    git tag {{version}}
+    git checkout {{version}}
+    git push --tags -f
+    python3 setup.py sdist
+    twine upload dist/pystencils_autodiff-{{version}}.tar.gz
+    git checkout master
+    
+wheel_release version: test
+    git tag {{version}}
+    git checkout {{version}}
+    git push --tags -f
+    python3 setup.py bdist_wheel
+    twine upload dist/pystencils_autodiff-{{version}}-cp37-cp37m-linux_x86_64.whl
+    git checkout master