remove unused color definitions/layout to make lint happy again

src/main/res/layout/simple_dialog_list_item.xml

@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<TextView xmlns:android="http://schemas.android.com/apk/res/android"
-    android:id="@android:id/text1"
-    android:layout_width="match_parent"
-    android:layout_height="wrap_content"
-    android:textAppearance="?android:attr/textAppearanceListItemSmall"
-    android:textColor="@color/dialog_list_item"
-    android:textSize="@dimen/two_line_primary_text_size"
-    android:gravity="center_vertical"
-    android:paddingLeft="@dimen/standard_padding"
-    android:paddingRight="@dimen/standard_padding"
-    android:minHeight="@dimen/simple_dialog_list_item_layout_size"/>

src/main/res/values/colors.xml

@@ -24,24 +24,16 @@
     <color name="list_item_lastmod_and_filesize_text">@color/secondaryTextColor</color>
     <color name="black">#000000</color>
     <color name="white">#FFFFFF</color>
-    <color name="white2">#F7F7F7</color>
     <color name="fab_white">#fafafa</color>
-    <color name="white_pressed">#f1f1f1</color>
-    <color name="half_black">#808080</color>
     <color name="black_semi_transparent">#B2000000</color>
     <color name="textColor">@color/black</color>
-    <color name="drawerMenuTextColor">#000000</color>
     <color name="list_divider_background">#eee</color>
     <color name="filelist_icon_backgorund">#DDDDDD</color>
     <color name="dark_background_text_color">#EEEEEE</color>
-    <color name="secondary_button_color">#D6D7D7</color>
     <color name="transparent">#00000000</color>
     <color name="secondaryTextColor">#a0a0a0</color>
-    <color name="listItemHighlighted">#f8f8f8</color>
-    <color name="highlightTextColor">#55739a</color>
 
     <!-- Colors -->
-    <color name="dialog_list_item">#1F1F1F</color>
     <color name="standard_grey">#757575</color>
 
     <!-- standard material color definitions -->