add grid display mode (#143)

Author: Raival-e

app/src/main/java/com/raival/compose/file/explorer/screen/main/tab/files/misc/ViewType.kt

@@ -0,0 +1,5 @@
+package com.raival.compose.file.explorer.screen.main.tab.files.misc
+
+enum class ViewType {
+    COLUMNS, GRID
+}