HTTP API for climate sensor

Added the HTTP API for the climate sensor

HTTP GET    /sensor/climate/temperature -- Get temperature of climate sensor in celsius, fahrenheit and kelvin

This returns data in the following format...

HTTP/1.0 200 OK
Access-Control-Allow-Origin: *
Content-Type: application/json
Server: Webduino/1.7

{
    "category": "sensor",
    "command": "climate",
    "key": "temperature",
    "success": true,
    "value": {
        "celsius": 22.0,
        "fahrenheit": 71.6,
        "kelvin": 295.15
    }
}