Migrate to python (#265)

* Add initial python migration

* Add pylint

* Add pre-commit

* Add Dockerfile

* Add expression matching

* Use shelve to store previous matches

* Add notifications

* Calculate post age

* Update README.md

rfd_notify/models/offer.py

@@ -0,0 +1,8 @@
+class Offer:
+    # pylint: disable=unused-argument
+    def __init__(self, dealer_name, url, **kwargs):
+        self.dealer_name = dealer_name
+        self.url = url
+
+    def __repr__(self):
+        return f"Offer({self.url})"