Quickstart: add long press sets default (#7048)

add wiki reference

frontend/ui/quickstart.lua

@@ -36,6 +36,8 @@ Turning pages can be done either by swiping left and right or by single taps on
 
 ## Menu <a id="menu"></a>
 
+Most menu items will show more information about what they do by long pressing on the item.
+
 ### Main <a id="main-menu"></a>
 
 ![Menu](../resources/icons/mdlight/appbar.menu.svg) You can always view this quickstart guide again through *Help* → *Quickstart guide* in the top right menu.
@@ -53,6 +55,13 @@ In the file browser, you can tap on any file to open it. Long press on any file
 
 Once you have found the folder you have your books listed in, you can long press the selection that opens that folder and you should see a message box popup with the option to **Set as HOME directory**.
 
+## Defaults <a id="defaults"></a>
+
+If you long press an option KOReader will prompt you to set it as the global default.
+
+## Wiki <a id="wiki"></a>
+
+Please refer to the wiki at <a href="https://github.com/koreader/koreader/wiki">https://github.com/koreader/koreader/wiki</a> for more documentation.
 
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 Generated by KOReader %1.