fix #120, reopen the proper folder after rotating the device

app/src/main/kotlin/com/simplemobiletools/filemanager/activities/MainActivity.kt

@@ -44,7 +44,9 @@ class MainActivity : SimpleActivity() {
             isPickMultipleIntent = intent.getBooleanExtra(Intent.EXTRA_ALLOW_MULTIPLE, false)
         }
 
-        tryInitFileManager()
+        if (savedInstanceState == null) {
+            tryInitFileManager()
+        }
         checkWhatsNewDialog()
         checkIfRootAvailable()
         storeStateVariables()

app/src/main/kotlin/com/simplemobiletools/filemanager/fragments/ItemsFragment.kt

@@ -22,6 +22,7 @@ import com.simplemobiletools.filemanager.dialogs.CreateNewItemDialog
 import com.simplemobiletools.filemanager.extensions.config
 import com.simplemobiletools.filemanager.extensions.isPathOnRoot
 import com.simplemobiletools.filemanager.extensions.openFile
+import com.simplemobiletools.filemanager.helpers.PATH
 import com.simplemobiletools.filemanager.helpers.RootHelpers
 import com.stericson.RootTools.RootTools
 import kotlinx.android.synthetic.main.items_fragment.*
@@ -58,6 +59,19 @@ class ItemsFragment : Fragment(), ItemsAdapter.ItemOperationsListener, Breadcrum
         }
     }
 
+    override fun onSaveInstanceState(outState: Bundle) {
+        outState.putString(PATH, currentPath)
+        super.onSaveInstanceState(outState)
+    }
+
+    override fun onViewStateRestored(savedInstanceState: Bundle?) {
+        super.onViewStateRestored(savedInstanceState)
+        if (savedInstanceState != null) {
+            currentPath = savedInstanceState.getString(PATH)
+            storedItems.clear()
+        }
+    }
+
     override fun onResume() {
         super.onResume()
         context!!.updateTextColors(mView as ViewGroup)