Extract hardcoded strings from layouts

app/src/main/res/layout/reader_settings_sheet.xml

@@ -27,7 +27,7 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginLeft="16dp"
-        android:text="Pull up for more options"
+        android:text="@string/reader_pull_up_for_more_options"
         android:textColor="?android:attr/textColorHint"
         app:layout_constraintLeft_toRightOf="@id/general_prefs"
         app:layout_constraintTop_toTopOf="@id/general_prefs" />

app/src/main/res/values/strings.xml

@@ -435,6 +435,7 @@
     <string name="transition_no_previous">There\'s no previous chapter</string>
     <string name="transition_pages_loading">Loading pages…</string>
     <string name="transition_pages_error">Failed to load pages: %1$s</string>
+    <string name="reader_pull_up_for_more_options">Pull up for more options</string>
 
     <!-- Recent manga fragment -->
     <string name="recent_manga_source">%1$s - Ch.%2$s</string>
@@ -507,4 +508,4 @@
     <string name="channel_library">Library</string>
     <string name="channel_downloader">Downloader</string>
 
-</resources>
+</resources>