[RTL UI] Bidi-wrap filenames, paths, urls, metadata

bidi.lua:
- Revert "Alias everything to Bidi.nowrap() when in LTR UI,
  as using LTR isolates seems uneeded when already LTR" (part
  of a628714f) which was a wrong assumption: we need proper
  wrappers for all things paths. Enhance some of these wrappers.
- Fix GetText RTL wrapping which was losing empty lines and
  trailing \n.

- Wrap all paths, directories, filenames in the code with
  these wrappers.
- Wrap all book metadata (title, authors...) with BD.auto(),
  as it helps fixing some edge cases (like open/close quotation
  marks which are not considered as bracket types by FriBiDi).
  (Needed some minor logic changes in CoverBrowser.)

- Tweak hyphenation menu text
- Update forgotten SortWidget for UI mirroring
- KoptConfig: update "justification" index for RTL re-ordering,
  following the recent addition of the page_gap_height option.

plugins/evernote.koplugin/main.lua

@@ -1,3 +1,4 @@
+local BD = require("ui/bidi")
 local InputContainer = require("ui/widget/container/inputcontainer")
 local LoginDialog = require("ui/widget/logindialog")
 local InfoMessage = require("ui/widget/infomessage")
@@ -242,7 +243,7 @@ For Windows: netsh interface portproxy add listeningaddress:0.0.0.0 listeningpor
 For Linux: $socat tcp-listen:41185,reuseaddr,fork tcp:localhost:41184
 
 For more information, please visit https://github.com/koreader/koreader/wiki/Evernote-export.]])
-                            ,DataStorage:getDataDir())
+                            , BD.dirpath(DataStorage:getDataDir()))
                             })
                         end
                     }
@@ -595,7 +596,7 @@ function EvernoteExporter:exportClippings(clippings)
         end
     end
     if (self.html_export or self.txt_export) and export_count > 0 then
-        msg = msg .. T(_("\nNotes can be found in %1/."), realpath(self.clipping_dir))
+        msg = msg .. T(_("\nNotes can be found in %1/."), BD.dirpath(realpath(self.clipping_dir)))
     end
     UIManager:show(InfoMessage:new{ text = msg })
 end