Refactor plot_api exports

[archmoj]

plot_api function calls & exports are a bit unclear. We should spend some time refactoring the export to have something like this:

module.exports = {
    animate: animate,
    addFrames: addFrames,
    deleteFrames: deleteFrames,

    addTraces: addTraces,
    deleteTraces: deleteTraces,
    extendTraces: extendTraces,
    moveTraces: moveTraces,
    prependTraces: prependTraces,

    newPlot: newPlot,
    plot: plot,
    purge: purge,

    react: react,
    redraw: redraw,
    relayout: relayout,
    restyle: restyle,

    setPlotConfig: setPlotConfig,

    update: update,

    _guiRelayout: guiEdit(relayout),
    _guiRestyle: guiEdit(restyle),
    _guiUpdate: guiEdit(update),

    _storeDirectGUIEdit: _storeDirectGUIEdit
};