Add arrows

Change-Id: I250a30cafacb5ddfd7c87d5c11ab7c0ead923dd0
diff --git a/src/all/allpost.xfst b/src/all/allpost.xfst
index 6ea6dcf..32e7a90 100644
--- a/src/all/allpost.xfst
+++ b/src/all/allpost.xfst
@@ -16,6 +16,9 @@
 ! XML entities
 source all/entities.xfst
 
+! Arrows
+define Arrows [Alldash ">" | "<" Alldash];
+
 ! Technical protocols
 source all/protocols.xfst