remove SPP demo code, add EasyCloud service

1. SPP demo code not needed, removed;
2. add EasyCloud service for data transfer between:
   Module <==> EasyCloud
add LiMu LED control

add LiMu LED control CMD
fix bug: usart baudrate set && LED response bug;

fix:
1. MVD usart baudrate set by ConfigServer(EasyLink);
2. LED no response to cloud bug fixed;
3. change Module display name "WECHAT".
add auto activate mechanism in MVD

1. move auto activate mechanism into MVD main thread;
2. add activate mechanism enable/disable by macro.
fix bug: restoreDefault

buffer must be memset before set new value.
add MVD lib for SPP demo

1. use MVD static lib instead of  EasyCloud && MVD source code for
users;
2. add MVD usart baudrate set by Easylink;
3. use MVDMsgProtocol to do LiMu SmartLED message transform:
dev(usart) <==> cloud(json).
modify default ssid/userkey to connect.

use Airkiss to set ssid/userkey to connect.
update MVD_LIB

changeLog:
change MVD cloud connect notify message  (to App) to JSON:
{"MVDCloud":"connected"}