Add Attribute class unit tests

This pull request:

- Adds the comparison operators to the following classes:

 -- Attribute.AttributeName class

- Fixes bug in the "_create_cryptographic_parameters" function when "None" type parameters are used

- Adds read, write, and comparator unit tests for the Attribute class in the /kmip/core/objects.py file

Signed-off-by: Hadi Esiely <hadi.esiely-barrera@jhuapl.edu>

kmip/core/objects.py

@@ -49,6 +49,21 @@ class Attribute(Struct):
             super(Attribute.AttributeName, self).__init__(
                 value, Tags.ATTRIBUTE_NAME)
 
+        def __eq__(self, other):
+            if isinstance(other, Attribute.AttributeName):
+                if self.value != other.value:
+                    return False
+                else:
+                    return True
+            else:
+                NotImplemented
+
+        def __ne__(self, other):
+            if isinstance(other, Attribute.AttributeName):
+                return not (self == other)
+            else:
+                return NotImplemented
+
     class AttributeIndex(Integer):
 
         def __init__(self, value=None):