feat(options): Intent to ship legend.item.tile.type

[netil]

Issue

#2874

Details

Implement 'circle' shape for legend item tile.

legend: {
    item: {
        tile: {
            type: "circle",  // default 'rectangle'
            r: 10,  // setup radius of circle item type
        }
    }
}

[coveralls]

Coverage decreased (-0.005%) to 90.536% when pulling 2bb9878 on netil:legendItemType#2874 into 1490b63 on naver:master.