IMPORTANT: import path changed, it's now: "from polymorphic import PolymorphicModel, ..."

- added python2.4 compatibility. Contributed by Charles Leifer. Thanks!
- general reorganization of the code - there is no single polymorphic.py module anymore,
  so d-p now needs to be installed as a regular Django app
- polymorphic.VERSION/get_version added
- version numbering started: V0.5 beta

test_all_python_versions

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+function testit {
+    if which $1 ; then
+        if ! $1 manage.py test ; then echo ERROR ; exit 10 ; fi
+    else
+        echo "### $1 is not installed!"
+    fi
+}
+
+testit python2.4
+testit python2.5
+testit python2.6
+