Fix duplicated string entry

BasicLanguage[1225] occurred twice, which resulted in instances of
"Select" being overwritten with "None" for the select button on some
folder selection dialog boxes. This creates a new BasicLanguage[1234]
for the "None" entry and updates the references to that string,
which fixes the button on the folder selection dialog boxes.
Merge pull request #462 from tomstokes/master

Fix duplicated string entry which caused folder select dialogs to show incorrect button label
Set code signing ID to match existing certificate