backport to python 2.6, add it travis platforms and to pypi metadata

.travis.yml

@@ -1,5 +1,6 @@
 language: python
 python:
+    - "2.6"
     - "2.7"
     - "pypy"
 install:

nsupdate/utils/log.py

@@ -64,7 +64,7 @@ def _get_elementdict(dct, basename, excluded=None):
     if excluded is None:
         excluded = set()
     names = set(dct) - set(excluded)
-    return {basename + name: dct[name] for name in names}
+    return dict((basename + name, dct[name]) for name in names)
 
 
 def _build_request_info(request):

setup.py

@@ -65,6 +65,7 @@ setup(
         'License :: OSI Approved :: BSD License',
         'Operating System :: OS Independent',
         'Programming Language :: Python',
+        'Programming Language :: Python :: 2.6',
         'Programming Language :: Python :: 2.7',
         'Topic :: Internet :: Name Service (DNS)',
     ],