[gcalctool] Add note why we can't use T_DIVIDE

[Robert Ancell <rancell src gnome org>]

commit c9fe1142fe806425a079b248d4d441f75106a50e
Author: Robert Ancell <robert ancell canonical com>
Date:   Wed Aug 22 08:59:15 2012 +1200

    Add note why we can't use T_DIVIDE

 src/prelexer.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/prelexer.h b/src/prelexer.h
index 4dd21e9..c206656 100644
--- a/src/prelexer.h
+++ b/src/prelexer.h
@@ -36,7 +36,7 @@ typedef enum
     T_ADD,			//Plus
     T_SUBTRACT,			//Minus
     T_MULTIPLY,			//Multiply
-    T_DIV,			//Divide
+    T_DIV,			//Divide (note can't use T_DIVIDE as it is defined in *BSD as an "integer divide fault" trap type value)
     T_MOD,			//Modulus
     T_L_FLOOR,			//Floor ( Left )
     T_R_FLOOR,		//20	//Floor ( Right )