[Feature Request] Better Colormap UI

[johnsbuck]

As a user, I would like to be able to have more control over colors that are being added in the Heatmap settings page. That way, I don't have to look somewhere else to create a color array and can edit my pre-existing colormaps if I want to change a color.

Some features that would be nice include the following:

Edit Button

An edit button to bring up the previous colormap would allow easy editing similar to adding new colormaps.

Color Picker UI

Adding a color picker UI would allow easy insertion instead of forcing a specific color array format.

[johnsbuck]

Another nice addition would be a simple color gradient, where you could set the starting and ending color for a gradient, the number of colors, and then just using lerp to create the in-between colors.