docs: fix sphinx formatting and syntax

src/aws_encryption_sdk/keyrings/aws_kms/__init__.py

@@ -60,7 +60,7 @@ class KmsKeyring(Keyring):
     If you specify ``is_discovery=True`` the keyring will be a KMS discovery keyring,
     doing nothing on encrypt and attempting to decrypt any AWS KMS-encrypted data key on decrypt.
 
-    .. notice::
+    .. note::
 
         You must either set ``is_discovery=True`` or provide key IDs.
 

src/aws_encryption_sdk/keyrings/raw.py

@@ -79,7 +79,8 @@ class RawAESKeyring(Keyring):
     :param WrappingAlgorithm wrapping_algorithm: Wrapping Algorithm with which to wrap plaintext data key.
 
     .. note::
-    Only one wrapping key can be specified in a Raw AES Keyring
+
+        Only one wrapping key can be specified in a Raw AES Keyring
     """
 
     key_namespace = attr.ib(validator=instance_of(six.string_types))

src/aws_encryption_sdk/structures.py

@@ -31,7 +31,7 @@
 class MasterKeyInfo(object):
     """Contains information necessary to identify a Master Key.
 
-    .. notice::
+    .. note::
 
         The only keyring or master key that should need to set ``key_name`` is the Raw AES keyring/master key.
         For all other keyrings and master keys, ``key_info`` and ``key_name`` should always be the same.