semicolon is minor keyword (see also 29f1e53f9937);

--- a/src/Pure/Isar/token.scala	Sat Jan 25 16:45:13 2014 +0100
+++ b/src/Pure/Isar/token.scala	Sat Jan 25 16:46:39 2014 +0100
@@ -108,7 +108,7 @@
     else source
 
   def text: (String, String) =
-    if (is_command && source == ";") ("terminator", "")
+    if (is_keyword && source == ";") ("terminator", "")
     else (kind.toString, source)
 }