Development - generic_wattmeter & generic_webcam protocol

Hi! This is my first contribution to pilight!

generic_wattmeter protocol is my first aproximation to a efergy_wattmeter protocol we can use it with:
pilight-send -p generic_wattmeter -i 10 -w 1000 (w = watts * 100 to avoid decimal problems)

and a config example:

                "Wattmetter": {
                        "name": "Wattmetter",
                        "protocol": [ "generic_wattmeter" ],
                        "id": [{
                                "id": 10,
                                "coin": "eur",
                                "price": 456 //price per watt * 1000 (to avoid decimal problems)
                        }],
                        "watt": 100000,
                        "settings": {
                                "coin": 1, //show coin
                                "watt": 1, //show watt
                                "price": 1, //show price (watt * price)
                        }
                }

and generic_webcam protocol:

                "Webcam": {
                        "name": "Webcam",
                        "protocol": [ "generic_webcam" ],
                        "id": [{
                                "id": 60,
                                "url": "http://xxxxxxxxxx" //image webcam url
                        }],
                        "settings": {
                                "interval": 500 //image refresh interval
                        }
                }