[Lens] Color options for string cells in tables

[teresaalvarezsoler]

Describe the feature: Users would like to have the ability to add colors to text/cells (non-numeric) in Lens Tables based on categorical values. This is only possible now for numerical values.

Describe a specific use case for the feature: Some use cases include setting colours for scales (high, med, low) or differentiating elements by colour (e.g. different cluster names, services, hosts, etc.)

Out of scope Intervals, IP addresses