发送 Email 并在 body 中直接嵌入图片

<appSettings>
	<add key="SMTP" value="SMTP Address"/>  //like mail.gmail.com
	<add key="MailFrom" value="Mail From"/>
	<add key="Port" value="Port Number"/> //usually 25
	<add key="MailUserName" value="user name of the mail from which the mail will be sent"/>
	<add key="MailPwd" value="Password"/>
	<add key="To" value="To whom you're sending the mail"/>
	<add key="CC" value="If there's any cc to add"/>
</appSettings>