add CoCo checker for all import types

[Hendrik7889]

Unsure about correct folders
Unsure about the correct way of adding CoCos with muliple implemnts

    // CDImport Statements
    CDOnlyResolvableImportStatements coCo = new CDOnlyResolvableImportStatements();
    checker.addCoCo((CDBasisASTCDTargetImportStatementCoCo) coCo); 
    checker.addCoCo((MCBasicTypesASTMCImportStatementCoCo) coCo);

Also didnt know how i should test targetimports