Continuous color map

[nf-s]

Continuous color map

Example http://ci.terria.io/continuous-color-map/#share=s-14cIDS8sGwd5gtkumJoU5C7sjt4

#3441

• Moved TableStyle.colorMap into TableColorMap
• Replaced colorbrewer.json with d3-scale-chromatic - we now support d3 color scales (in addition to color brewer) - see https://github.com/d3/d3-scale-chromatic
• Added ContinuousColorMap - it will now be used by default for scalar columns
  • To use DiscreteColorMap - you will need to set numberOfBins to something other than 0.
• TableColorMap default color palette for scalar columns is not Reds instead of RdYlOr
• Legends for scalar columns will now calculate optimal numberFormatOptions.maximumFractionDigits and numberFormatOptions.minimumFractionDigits

Todo

• Fix Minimum and maximum values must be different.

Checklist

• There are unit tests to verify my changes are correct or unit tests aren't applicable (if so, write quick reason why unit tests don't exist)
• I've updated CHANGES.md with what I changed.

[na9da]

@nf-s looks awesome! This is definitely a great enhancement.

Setting an invalid value for colorPalette results in app crash.

I'll update if I find any more problems.