Minor cleanup

mapdb/src/main/scala/lighdb/storage/mapdb/MapDBStore.scala

@@ -41,12 +41,4 @@ case class MapDBStore(directory: Option[Path]) extends ObjectStore {
   override def commit(): IO[Unit] = IO(db.commit())
 
   override def truncate(): IO[Unit] = IO(map.clear())
-}
-
-trait SharedMapDBSupport extends ObjectStoreSupport {
-  this: LightDB =>
-
-  private lazy val shared: MapDBStore = MapDBStore(directory.map(_.resolve("store")))
-
-  override def store[D <: Document[D]](collection: Collection[D]): ObjectStore = shared
 }

mapdb/src/main/scala/lighdb/storage/mapdb/SharedMapDBSupport.scala

@@ -0,0 +1,13 @@
+package lighdb.storage.mapdb
+
+import lightdb.collection.Collection
+import lightdb.store.{ObjectStore, ObjectStoreSupport}
+import lightdb.{Document, LightDB}
+
+trait SharedMapDBSupport extends ObjectStoreSupport {
+  this: LightDB =>
+
+  private lazy val shared: MapDBStore = MapDBStore(directory.map(_.resolve("store")))
+
+  override def store[D <: Document[D]](collection: Collection[D]): ObjectStore = shared
+}