Get/Set WebDav port
Input
[ESP191]<port> json=<no> pwd=<admin password>
- 
json=no the output format can be in JSON or plain text 
- 
pwd= the admin password if authentication is enabled 
- 
port - if port is empty, it will display current port
- if port is not empty, it will set the port
 
Output
- In json format
- cmdId of requested command, should be- 191
- statusstatus of command, should be- ok
- datacontent of response, here the port
