Expose that settable properties are so. (#3472)

* Expose that settable properties are so.

Closes #2610.

storage/google/cloud/storage/bucket.py

@@ -608,11 +608,14 @@ def id(self):
 
     @property
     def lifecycle_rules(self):
-        """Lifecycle rules configured for this bucket.
+        """Retrieve or set lifecycle rules configured for this bucket.
 
         See https://cloud.google.com/storage/docs/lifecycle and
              https://cloud.google.com/storage/docs/json_api/v1/buckets
 
+        :setter: Set lifestyle rules for this bucket.
+        :getter: Gets the lifestyle rules for this bucket.
+
         :rtype: list(dict)
         :returns: A sequence of mappings describing each lifecycle rule.
         """
@@ -621,6 +624,14 @@ def lifecycle_rules(self):
 
     @lifecycle_rules.setter
     def lifecycle_rules(self, rules):
+        """Set lifestyle rules configured for this bucket.
+
+        See https://cloud.google.com/storage/docs/lifecycle and
+             https://cloud.google.com/storage/docs/json_api/v1/buckets
+
+        :type entries: list of dictionaries
+        :param entries: A sequence of mappings describing each lifecycle rule.
+        """
         self._patch_property('lifecycle', {'rule': rules})
 
     location = _scalar_property('location')
@@ -721,10 +732,13 @@ def self_link(self):
 
     @property
     def storage_class(self):
-        """Retrieve the storage class for the bucket.
+        """Retrieve or set the storage class for the bucket.
 
         See https://cloud.google.com/storage/docs/storage-classes
 
+        :setter: Set the storage class for this bucket.
+        :getter: Gets the the storage class for this bucket.
+
         :rtype: str or ``NoneType``
         :returns: If set, one of "MULTI_REGIONAL", "REGIONAL",
                   "NEARLINE", "COLDLINE", "STANDARD", or
@@ -767,6 +781,9 @@ def versioning_enabled(self):
         See  https://cloud.google.com/storage/docs/object-versioning for
         details.
 
+        :setter: Update whether versioning is enabled for this bucket.
+        :getter: Query whether versioning is enabled for this bucket.
+
         :rtype: bool
         :returns: True if enabled, else False.
         """