UI: fix interaction time

Use system locale to correctly display interactions time in different
languages.

Change-Id: Ib70c3be46ccef36a001c50b99e058aa5d12f0837
Reviewed-by: Andreas Traczyk <andreas.traczyk@savoirfairelinux.com>

src/MessagesVC.mm

@@ -668,6 +668,7 @@ typedef NS_ENUM(NSInteger, MessageSequencing) {
 -(NSString *)timeForMessage:(NSDate*) msgTime {
     NSDate *today = [NSDate date];
     NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init];
+    [dateFormatter setLocale:[[NSLocale alloc] initWithLocaleIdentifier:[[NSLocale currentLocale] localeIdentifier]]];
     if ([[NSCalendar currentCalendar] compareDate:today
                                            toDate:msgTime
                                 toUnitGranularity:NSCalendarUnitYear]!= NSOrderedSame) {