Added some Docs

src/main/java/device/fitbitdata/Sleep.java

@@ -0,0 +1,21 @@
+package device.fitbitdata;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import java.util.Map;
+
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class Sleep {
+
+    private int minutesAsleep;
+
+    public int getMinutesAsleep() {
+        return minutesAsleep;
+    }
+
+    @JsonProperty("summary")
+    public void setMinutesAsleep(Map<String, Object> map) {
+        minutesAsleep = (int) map.get("totalMinutesAsleep");
+    }
+}