add CoCo for all import types

[Hendrik7889]

• Errors on unresolvable imports
• Warns on unresolvable targetimports
• Ignores star imports

Closes #118

[github-actions]

✔️ Changes pass the MontiVerse

Project	Status

details

Project	Status
montitransruntime	⏩
montiarc	✅
umlp_experiments	✅
umlp_tool	✅
sd	✅
montifun	✅
fd	✅
automaton_diff	✅
automaton	✅
sc	✅
guidsl	✅
artifacts	✅
ocl	✅
od	✅
ucd	⏩
langexperiments	⏩
json	⏩
xml	⏩
cd2gui	✅
mlc	⏩
monticore_future	✅
cd4analysis	✅
monticore_basic	⏩
class2mc	⏩
secommons	⏩

The MontiVerse is a collection of (internal and public) language projects.