Ignore special kotlin collection types (#2130)

Kotlin prefers(emits compiler warnings if not) the built-in types
e.g. Set and MutableSet instead of the java.util.* variety. This
patch removes the imports for those, so the built-in varieties are
used.

kotlin-querybean-generator/src/main/java/io/ebean/querybean/generator/SimpleQueryBeanWriter.java

@@ -8,6 +8,9 @@ import java.io.FileWriter;
 import java.io.IOException;
 import java.io.Writer;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Set;
@@ -42,6 +45,23 @@ class SimpleQueryBeanWriter {
     "kotlin.Char"
   };
 
+  // These are special classes under Kotlin, and are auto-imported, same as
+  // java.lang under Java
+  private static final Set<String> kotlinBlackListedImports = Collections.unmodifiableSet(
+    new HashSet<>(
+      Arrays.asList(
+        "java.util.ArrayList",
+        "java.util.HashMap",
+        "java.util.HashSet",
+        "java.util.LinkedHashMap",
+        "java.util.LinkedHashSet",
+        "java.util.List",
+        "java.util.Map",
+        "java.util.Set"
+      )
+    )
+  );
+
   private final Set<String> importTypes = new TreeSet<>();
 
   private final List<PropertyMeta> properties = new ArrayList<>();
@@ -158,6 +178,7 @@ class SimpleQueryBeanWriter {
         importTypes.add(kotlinTypes[i]);
       }
     }
+    importTypes.removeAll(kotlinBlackListedImports);
   }
 
   private boolean isEntity() {