Added a sensor example in C using polling

examples/c/sensors/polling/Makefile

@@ -0,0 +1,13 @@
+CC=gcc
+CFLAGS=-Wall -ltelldus-core
+
+OBJS = main.o
+
+all: ${OBJS}
+	${CC} -o sensor ${CFLAGS} ${OBJS}
+
+main.c:
+	${CC} ${CFLAGS} -c main.c
+
+clean:
+	rm -f sensor main.o

examples/c/sensors/polling/main.c

@@ -0,0 +1,38 @@
+#include <telldus-core.h>
+#include <time.h>
+#include <stdio.h>
+
+const int DATA_LENGTH = 20;
+
+int main(void) {
+	char protocol[DATA_LENGTH], model[DATA_LENGTH];
+	int sensorId = 0, dataTypes = 0;
+	char value[DATA_LENGTH];
+	char timeBuf[80];
+	time_t timestamp = 0;
+
+	
+	tdInit();
+
+	while(tdSensor(protocol, DATA_LENGTH, model, DATA_LENGTH, &sensorId, &dataTypes) == TELLSTICK_SUCCESS) {
+		//Print the sensor
+		printf("%s,\t%s,\t%i\n", protocol, model, sensorId);
+
+		//Retrieve the values the sensor supports
+		if (dataTypes & TELLSTICK_TEMPERATURE) {
+			tdSensorValue(protocol, model, sensorId, TELLSTICK_TEMPERATURE, value, DATA_LENGTH, (int *)&timestamp);
+			strftime(timeBuf, sizeof(timeBuf), "%Y-%m-%d %H:%M:%S", localtime(&timestamp));
+			printf("Temperature:\t%sº\t(%s)\n", value, timeBuf);
+		}
+		if (dataTypes & TELLSTICK_HUMIDITY) {
+			tdSensorValue(protocol, model, sensorId, TELLSTICK_HUMIDITY, value, DATA_LENGTH, (int *)&timestamp);
+			strftime(timeBuf, sizeof(timeBuf), "%Y-%m-%d %H:%M:%S", localtime(&timestamp));
+			printf("Humidity:\t%s%%\t(%s)\n", value, timeBuf);
+		}
+		printf("\n");
+	}
+
+	tdClose();
+
+	return 0;
+}