Python 3 Compatibility with __version__.py

The 'basestring' keyword was removed from __version__.py making Python <= 3.3 compatible.

Author: mmellison

eve_mongoengine/__version__.py

@@ -1,8 +1,12 @@
 # Project Version
 
+# This file must remain compatible with
+# both Python >= 2.6 and Python 3.3+
+
 VERSION = (0, 1, 0)     # 0.1.0
 
 def get_version():
-    if isinstance(VERSION[-1], basestring):
-        return '.'.join(map(str, VERSION[:-1])) + VERSION[-1]
-    return '.'.join(map(str, VERSION))
+    if isinstance(VERSION[-1], int):
+        return '.'.join(map(str, VERSION))
+    return '.'.join(map(str, VERSION[:-1])) + VERSION[-1]
+