R221b2t20AU Release Note

1. fix our device can't get the ip from wan in RETH mode.
2. fix AU static route entry will be changed problem when user use pppoe to connect, 
    when device get the ip , it will cause route entry to be re-calculated. This will make the original 
    static route to be forwarded to ppp, without redirect to where user wants.  
    This bug will only happen on where lan and wan are same ip with different subnet mask 
3. merge new ethe MII patch, 
4. remove data transmit test item on diagnose page (which is causing confusion for users)


R221b2t17AU Release Note

1. DMZ IP Address enabled
2. SNMP capability enabled

