如何使用shell脚本在xml文件中添加新标记？

I have an xml file like

我有一个像xml这样的文件

<changeSet id="1" author="naveen" dbms="oracle">
      <sqlFile path="/appl/Liquibase/sql/IntialVersion.sql" />
    </changeSet>
    <changeSet id="2" author="naveen"  dbms="oracle">
      <sqlFile path="/appl/Liquibase/sql/FirstRev.sql" />
    </changeSet>
    <changeSet id="3" author="naveen"  dbms="oracle">
      <sqlFile path="/appl/Liquibase/sql/23_12_2011.sql" />
    </changeSet>
<chan