Rename token_symbol to token_bound

Change-Id: I3e4f35c1fc65b542e948659d94437e818fc1f136
diff --git a/fomafile.go b/fomafile.go
index 8f8f046..9d7106c 100644
--- a/fomafile.go
+++ b/fomafile.go
@@ -409,10 +409,16 @@
 							auto.identity = number
 						}
 
+						// Deprecated
 					case "@_TOKEN_SYMBOL_@":
 						{
 							auto.tokenend = number
 						}
+
+					case "@_TOKEN_BOUND_@":
+						{
+							auto.tokenend = number
+						}
 					default:
 						{
 							// MCS not supported