Bugfix/normalize core comparisons (and Python 3 update fixes) (#952)

* Correct implementation of comparisons to be Pythonic

If a comparison cannot be made return NotImplemented, this allows the
Python interpreter to try other comparisons (eg __ieq__) and either
return False (in the case of __eq__) or raise a TypeError
exception (eg in the case of __lt__).

* Python 3 updates

* Add a more helpful message in exception if platform is not defined

* Added a basic pre-commit check

.pre-commit-config.yaml

@@ -0,0 +1,11 @@
+# See https://pre-commit.com for more information
+# See https://pre-commit.com/hooks.html for more hooks
+repos:
+-   repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v2.4.0
+    hooks:
+    -   id: trailing-whitespace
+    -   id: end-of-file-fixer
+    -   id: check-yaml
+    -   id: check-added-large-files
+    -   id: flake8