Added pyproject.toml

pyproject.toml

+[project]
+name = "alphapulldown-modelcif-converter"
+version = "0.0.1"
+requires-python = "==3.8"
+dependencies = [
+    "modelcif==0.8",
+]
+
+[tool.black]
+line-length = 80
+
+[tool.pylint.REPORTS]
+reports = "no"
+
+[tool.pylint.FORMAT]
+max-line-length = 81