OStatus: Add user bio as summary field

Fixes problem with bio federation.

lib/pleroma/web/ostatus/user_representer.ex

@@ -19,6 +19,7 @@ def to_simple_form(user) do
       {:"poco:preferredUsername", [nickname]},
       {:"poco:displayName", [name]},
       {:"poco:note", [bio]},
+      {:summary, [bio]},
       {:name, [nickname]},
       {:link, [rel: 'avatar', href: avatar_url], []}
     ] ++ banner

test/web/ostatus/user_representer_test.exs

@@ -18,6 +18,7 @@ test "returns a user with id, uri, name and link" do
     <poco:preferredUsername>#{user.nickname}</poco:preferredUsername>
     <poco:displayName>#{user.name}</poco:displayName>
     <poco:note>#{user.bio}</poco:note>
+    <summary>#{user.bio}</summary>
     <name>#{user.nickname}</name>
     <link rel="avatar" href="#{User.avatar_url(user)}" />
     """