gitdb2: init at 2.0.3

Also move gitdb and gitdb2 to the new python module structure.

pkgs/development/python-modules/gitdb2/default.nix

@@ -0,0 +1,23 @@
+{ lib, buildPythonPackage, fetchPypi, smmap2 }:
+
+buildPythonPackage rec {
+  pname = "gitdb2";
+  version = "2.0.3";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "02azg62mr99b7cllyjrly77np3vw32y8nrxpa2xjapiyaga2j3mn";
+  };
+
+  propagatedBuildInputs = [ smmap2 ];
+
+  # Bunch of tests fail because they need an actual git repo
+  doCheck = false;
+
+  meta = {
+    description = "Git Object Database";
+    maintainers = [ ];
+    homepage = https://github.com/gitpython-developers/gitdb;
+    license = lib.licenses.bsd3;
+  };
+}