pythonPackages.pony: init at 0.7.11

pony is an ORM library.

The main motivation for adding this package is to allow migrating
tribler to a newer version that supports python3.

Also adding myself to maintainers to not leave this one without, even
though I dont use it myself much, if anybody else feels like it fits their
interests, feel free to add yourselves.

maintainers/maintainer-list.nix

@@ -1484,6 +1484,16 @@
       }
     ];
   };
+  d-goldin = {
+    email = "dgoldin+github@protonmail.ch";
+    github = "d-goldin";
+    githubId = 43349662;
+    name = "Dima";
+    keys = [{
+      longkeyid = "rsa4096/BAB1D15FB7B4D4CE";
+      fingerprint = "1C4E F4FE 7F8E D8B7 1E88 CCDF BAB1 D15F B7B4 D4CE";
+    }];
+  };
   dadada = {
     name = "dadada";
     email = "dadada@dadada.li";