Add an option for an independent color for delimiters

[windless0530]

Just a suggestion:

Current behavior: each column with the following delimiter is an independent color
Expected behavior: each column without delimiter is an independent color, and all delimiters are of one independent color, light gray for example.

An option can be provided to turn this on and off.

[mechatroner]

Current behavior has one important advantage: when some fields have zero length they are still visible and distinguishable because of distinct coloring.

But I agree that coloring delimiter in some neutral (light gray) color can be implemented as a feature. Problem is: language grammars are not configurable (at least until microsoft/vscode#53885 is implemented). The only possible way to implement this, that I am aware of, is to use setDecorations VSCode Api.

BTW you can try to use Highlight extension, probably it can be configured to highlight delimiters in neutral color.