feat(mail): Add an option in Preferences to display full email instead of name alone in mailboxes

SoObjects/SOGo/SOGoUserDefaults.h

@@ -156,6 +156,9 @@ extern NSString *SOGoPasswordRecoverySecondaryEmail;
 - (void) setMailComposeFontSize: (int) newValue;
 - (int) mailComposeFontSize;
 
+- (void) setMailDisplayFullEmail: (BOOL *) newValue;
+- (BOOL *) mailDisplayFullEmail;
+
 - (void) setMailDisplayRemoteInlineImages: (NSString *) newValue;
 - (NSString *) mailDisplayRemoteInlineImages;