Color map prevents other color options

[adamocarolli]

Using a color set should not prevent using color options in layer data (ie. rgb values or hex codes).

// Passing in color mapping here 
const colors = [
    '#5e81ac',
    '#d08770',
    '#ebcb8b',
    '#81a1c1',
];
new GraferController(canvas, { points, colors layers });

// Prevents ability to change colors in layer data without using mapping
layer.edges.data.push(Object.assign({}, edge, {
    sourceColor: '#ebcb8b',
    targetColor: '#ebcb8b',
}));