Remove pointless #imports from .m and .h files

This was done with a brute-force approach, ensuring no additional
warnings from GCC 4.9 under x86_64.

UI/MailerUI/UIxMailToSelection.m

@@ -20,12 +20,9 @@
 */
 
 #import <Foundation/NSDictionary.h>
-#import <Foundation/NSEnumerator.h>
 
 #import <NGObjWeb/WORequest.h>
 #import <NGExtensions/NSNull+misc.h>
-#import <NGMail/NGMailAddress.h>
-#import <NGMail/NGMailAddressParser.h>
 
 #import <SOGoUI/UIxComponent.h>