Explicit "maxItems" property of meters

Two changes in this commit:
- All meters now explicitly specify "maxItems" property, even for just
  1 item. (Exception is "container" CPU meter classes, which use
  CUSTOM_METERMODE.)
- "maxItems" being 0 is now allowed. This will let bar meters and graph
  meters render an empty meter.

BatteryMeter.c

@@ -75,6 +75,7 @@ MeterClass BatteryMeter_class = {
    },
    .setValues = BatteryMeter_setValues,
    .defaultMode = TEXT_METERMODE,
+   .maxItems = 1,
    .total = 100.0,
    .attributes = BatteryMeter_attributes,
    .name = "Battery",

CPUMeter.c

@@ -312,8 +312,8 @@ MeterClass LeftCPUs2Meter_class = {
    .total = 100.0,
    .attributes = CPUMeter_attributes, 
    .name = "LeftCPUs2",
-   .description = "CPUs (1&2/4): first half in 2 shorter columns",
    .uiName = "CPUs (1&2/4)",
+   .description = "CPUs (1&2/4): first half in 2 shorter columns",
    .caption = "CPU",
    .draw = DualColCPUsMeter_draw,
    .init = AllCPUsMeter_init,

ClockMeter.c

@@ -34,6 +34,7 @@ MeterClass ClockMeter_class = {
    },
    .setValues = ClockMeter_setValues, 
    .defaultMode = TEXT_METERMODE,
+   .maxItems = 1,
    .total = 1440, /* 24*60 */
    .attributes = ClockMeter_attributes,
    .name = "Clock",

HostnameMeter.c

@@ -31,6 +31,7 @@ MeterClass HostnameMeter_class = {
    },
    .setValues = HostnameMeter_setValues, 
    .defaultMode = TEXT_METERMODE,
+   .maxItems = 0,
    .total = 100.0,
    .attributes = HostnameMeter_attributes,
    .name = "Hostname",

LoadAverageMeter.c

@@ -77,6 +77,7 @@ MeterClass LoadMeter_class = {
    },
    .setValues = LoadMeter_setValues, 
    .defaultMode = TEXT_METERMODE,
+   .maxItems = 1,
    .total = 100.0,
    .attributes = LoadMeter_attributes,
    .name = "Load",

Meter.c

@@ -132,12 +132,8 @@ Meter* Meter_new(struct ProcessList_* pl, int param, MeterClass* type) {
    this->h = 1;
    this->param = param;
    this->pl = pl;
-   char maxItems = type->maxItems;
-   if (maxItems == 0) {
-      maxItems = 1;
-   }
-   type->curItems = maxItems;
-   this->values = xCalloc(maxItems, sizeof(double));
+   type->curItems = type->maxItems;
+   this->values = xCalloc(type->maxItems, sizeof(double));
    this->total = type->total;
    this->caption = xStrdup(type->caption);
    if (Meter_initFn(this))
@@ -550,6 +546,7 @@ MeterClass BlankMeter_class = {
    },
    .setValues = BlankMeter_setValues,
    .defaultMode = TEXT_METERMODE,
+   .maxItems = 0,
    .total = 100.0,
    .attributes = BlankMeter_attributes,
    .name = "Blank",

SwapMeter.c

@@ -56,6 +56,7 @@ MeterClass SwapMeter_class = {
    },
    .setValues = SwapMeter_setValues, 
    .defaultMode = BAR_METERMODE,
+   .maxItems = 1,
    .total = 100.0,
    .attributes = SwapMeter_attributes,
    .name = "Swap",

TasksMeter.c

@@ -74,8 +74,8 @@ MeterClass TasksMeter_class = {
    },
    .setValues = TasksMeter_setValues, 
    .defaultMode = TEXT_METERMODE,
-   .total = 100.0,
    .maxItems = 4,
+   .total = 100.0,
    .attributes = TasksMeter_attributes, 
    .name = "Tasks",
    .uiName = "Task counter",

UptimeMeter.c

@@ -51,6 +51,7 @@ MeterClass UptimeMeter_class = {
    },
    .setValues = UptimeMeter_setValues, 
    .defaultMode = TEXT_METERMODE,
+   .maxItems = 1,
    .total = 100.0,
    .attributes = UptimeMeter_attributes,
    .name = "Uptime",