Adding ordereddict dependency of py26

Using the ordereddict package instead of odict

pyutilib/misc/pyyaml_util.py

@@ -20,7 +20,7 @@
 try:  # pragma no cover
     from collections import OrderedDict
 except ImportError:  # pragma no cover
-    from odict import OrderedDict
+    from ordereddict import OrderedDict
 try:
     from StringIO import StringIO
 except:

pyutilib/misc/xmltodict.py

@@ -22,7 +22,7 @@
     #OrderedDict = dict
     from collections import OrderedDict
 except ImportError:  # pragma no cover
-    from odict import OrderedDict
+    from ordereddict import OrderedDict
 
 try:  # pragma no cover
     _basestring = basestring

setup.py

@@ -42,6 +42,7 @@ def read(*rnames):
 requires=[ 'nose', 'six' ]
 if sys.version_info < (2,7):
     requires.append('argparse')
+    requires.append('ordereddict')
     requires.append('unittest2')
 
 setup(name="PyUtilib",