Redundant messages for unresolved module

[rodinaarssen]

Describe the bug

If a module name cannot be resolved, the line with the import statement is decorated with three warnings, of which the first two are implied by the last one. Squiglies are now in two colors, and one message would suffice.

Expected behavior A clear and concise description of what you expected to happen.

Screenshots

Desktop (please complete the following information):

• Context: Eclipse 2020-03
• Rascal Version 0.19.x (latest unstable)

[PaulKlint]

This is a fair point Rodin, I need to figure out how to filter such duplicates.

[PaulKlint]

This was already resolved for #1570 and #1570 in upcoming release.