drawCircle = function(color, lineWidth, percent) {
		percent = Math.min(Math.max(-1, percent || 0), 1);
		var isNegative = percent <= 0 ? true : false;

		ctx.beginPath();
		ctx.arc(0, 0, radius, 0, Math.PI * 2 * percent, isNegative);

		ctx.strokeStyle = color;
		ctx.lineWidth = lineWidth;

		ctx.stroke();
	}
Draw a circle around the center of the canvas
@param {strong} color     Valid CSS color string
@param {number} lineWidth Width of the line in px
@param {number} percent   Percentage to draw (float between -1 and 1)