Review text field highlighting

[arildm]

Currently, tokens are highlighted with blue on gray if their edge has manual.

We might want to also highlight deletions, insertions, whether the token has any labels etc.

[arildm]

As discussed in yesterday's meeting, deletion/insertion markup would be more obtrusive than helpful.

@elenavolodina I'm not sure what we said about marking up other aspects, like "is the token manual-marked" or "does it have any labels", do you remember? I think the general opinion was "the less markup, the better", shall we try with no markup at all? (Just to be clear, I'm talking about the text fields only, the spaghetti is fine.)

Related: in #125 we are also adding highlighting.

[arildm]

Anonymization: mark labeled tokens.

Normalization: no markup.

Correction annotation: mark insertions & deletions, moved tokens (= manual?), labeled tokens.