added begin and imports;

--- a/doc-src/isar.sty	Fri May 02 16:36:29 2008 +0200
+++ b/doc-src/isar.sty	Fri May 02 16:38:01 2008 +0200
@@ -27,6 +27,8 @@
 \newcommand{\isasymAND}{\isakeyword{and}}
 \newcommand{\isasymIS}{\isakeyword{is}}
 \newcommand{\isasymWHERE}{\isakeyword{where}}
+\newcommand{\isasymBEGIN}{\isakeyword{begin}}
+\newcommand{\isasymIMPORTS}{\isakeyword{imports}}
 
 \newcommand{\isarkeyword}[1]{{\mathord{\mathbf{#1}}}}
 \newcommand{\isarcmd}[1]{\isarkeyword{#1}}