parse SAN otherNames into OtherName instances rather than raising an exception

Test added.
diff --git a/docs/x509.rst b/docs/x509.rst
index f94f50e..eab1f53 100644
--- a/docs/x509.rst
+++ b/docs/x509.rst
@@ -695,6 +695,20 @@
 
         :type: :class:`ObjectIdentifier`
 
+.. class:: OtherName
+
+    .. versionadded:: 1.0
+
+    This corresponds to an "otherName."  An otherName has a type identifier and a value represented in binary DER format.
+
+    .. attribute:: type_id
+
+        :type: :class:`ObjectIdentifier`
+
+    .. attribute:: value
+
+        :type: `bytes`
+
 X.509 Extensions
 ~~~~~~~~~~~~~~~~