func NewGauge() *Gauge {
	g := &Gauge{
		Block:                   *NewBlock(),
		PercentColor:            ThemeAttr("gauge.percent.fg"),
		BarColor:                ThemeAttr("gauge.bar.bg"),
		Label:                   "{{percent}}%",
		LabelAlign:              AlignCenter,
		PercentColorHighlighted: ColorUndef,
	}
	g.Width = 12
	g.Height = 5
	return g
}
NewGauge return a new gauge with current theme.
package termui
import (
	"strconv"
	"strings"
)
const ColorUndef Attribute = Attribute(^uint16(0))
type Gauge struct {
	Block
	Percent                 int
	BarColor                Attribute
	PercentColor            Attribute
	PercentColorHighlighted Attribute
	Label                   string
	LabelAlign              Align
}