Added option to download page or set page as cover (#481)

* Added option to download page or set page as cover

* Removed network call now copies from page image

* Format fix + notification feedback

* Added code to prevent OutOfMemory error.  Made notification optional. Can now save image on long press. Bug fixes

* Now uses glide for notification

* Fixed webtoon page

* Fixes + API 16 support

* fixes

* Fixed API 24 FileProvider error

* Added page.ready check

* Indention

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

@@ -176,4 +176,16 @@
         <item>3</item>
     </string-array>
 
+    <string-array name="reader_image_options">
+        <item>@string/set_as_cover</item>
+        <item>@string/action_share</item>
+        <item>@string/action_save</item>
+    </string-array>
+
+    <string-array name="reader_image_options_values">
+        <item>0</item>
+        <item>1</item>
+        <item>2</item>
+    </string-array>
+
 </resources>