Visual clarity between Tab and Space characters in Moonshine-IDE editors

[rat-moonshine]

This mostly a brainstorming issue at this moment, and may needs proper planning/time-allocation when we'll really wants an implementation.

Currently, Moonshine-IDE editor not clearly describe, visually - between a Tab and a space.

In comparison with other IDE(s), distinguish Tab and space more clearly, visually, i.e.

We wants such clarity in Moonshine-IDE editors, as well.

[JoelProminic]

Here are examples where mixed tabs and spaces caused us trouble: #674 , #606

This probably should be a separate issue, but we should also think about adding more control over the indentation that Moonshine uses by default (tabs vs spaces, number of spaces). In the above YML example, it would be annoying to edit with more indentation because the tab key would add a full tab instead of the standard two-space indent.

[rat-moonshine]

I see I haven't looped this with @joshtynjala , I'm doing this now. In case he has any immediate idea/thought on this.

[joshtynjala]

I'm personally a fan of displaying tabs and spaces differently when they are selected.