LoadMeter: dynamically adjust color and total of bar

Change the color and total based on the actual 1min load value:

    < 1         : green and total of 1.0
    < cpu-count : yellow and total of cpu-count
    else        : red and total of 2*cpu-count

Closes: #32

Meter.h

@@ -100,6 +100,7 @@ struct Meter_ {
    int h;
    const ProcessList* pl;
    uint8_t curItems;
+   const int* curAttributes;
    double* values;
    double total;
    void* meterData;