Support for colorIndex property (allow custom line color codes)

Hello,

I have added a colorIndex property. This will allow users to specify colorN in any order they want. It's very usefull when having multiple series on the chart, and user needs some lines to be in specific color defined in the CSS file under color<colorIndex>.

Example:
............................................
dataOptions['main'].push({colorIndex: 1, data: extraDataSets[0]});
dataOptions['main'].push({colorIndex: 0, data: mainDataSet});
dataOptions['main'].push({colorIndex: 2, data: extraDataSets[1]});
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new xChart('custom', dataOptions, '#mychart');

Best regards,
Linas Pašviestis