Improve ABI version error reporting in the compiler

- only report ABI errors if there's at least one other error
- append additional helpful information to the "unresolved reference" error

compiler/tests/org/jetbrains/kotlin/cli/jvm/K2JvmCliTest.java

@@ -35,6 +35,11 @@ public class K2JvmCliTest extends CliBaseTest {
         executeCompilerCompareOutputJVM();
     }
 
+    @Test
+    public void wrongAbiVersionNoErrors() throws Exception {
+        executeCompilerCompareOutputJVM();
+    }
+
     @Test
     public void nonExistingClassPathAndAnnotationsPath() throws Exception {
         executeCompilerCompareOutputJVM();