增加mysql存储过程LOOP,REPAET,LEAVE,ITEARATE语法支持,以及支持BEGIN-END和WHILE语句标签支持

src/main/java/com/alibaba/druid/sql/parser/Token.java

@@ -131,6 +131,10 @@ public enum Token {
     // MySql procedure by:zz
     WHILE("WHILE"),
     DO("DO"),
+    LEAVE("LEAVE"),
+    ITERATE("ITERATE"),
+    REPEAT("REPEAT"),
+    UNTIL("UNTIL"),
     
     //postgresql
     WINDOW("WINDOW"),