Remove unnecessary fields from minimal cache

Lessen memory requirement: these enclosure informations will be required
(and retrieved from database) only when we display articles of folder.

Minimal cache is only used as a proxy marking if an article is (or isn't)
present in database, (un)read, (un)flagged, (un)deleted or revised.

Author: barijaona

Vienna/Sources/Database/Database.m

@@ -2005,7 +2005,7 @@ -(NSArray *)minimalCacheForFolder:(NSInteger)folderId
 
     FMDatabaseQueue *queue = self.databaseQueue;
     [queue inDatabase:^(FMDatabase *db) {
-        FMResultSet * results = [db executeQueryWithFormat:@"SELECT message_id, read_flag, marked_flag, deleted_flag, title, link, revised_flag, hasenclosure_flag, enclosure FROM messages WHERE folder_id=%ld", (long)folderId];
+        FMResultSet * results = [db executeQueryWithFormat:@"SELECT message_id, read_flag, marked_flag, deleted_flag, title, link, revised_flag FROM messages WHERE folder_id=%ld", (long)folderId];
         while ([results next]) {
             NSString * guid = [results stringForColumnIndex:0];
             BOOL read_flag = [results stringForColumnIndex:1].integerValue;
@@ -2014,8 +2014,6 @@ -(NSArray *)minimalCacheForFolder:(NSInteger)folderId
             NSString * title = [results stringForColumnIndex:4];
             NSString * link = [results stringForColumnIndex:5];
             BOOL revised_flag = [results stringForColumnIndex:6].integerValue;
-            BOOL hasenclosure_flag = [results stringForColumnIndex:7].integerValue;
-            NSString * enclosure = [results stringForColumnIndex:8];
 
             // Keep our own track of unread articles
             if (!read_flag) {
@@ -2030,8 +2028,6 @@ -(NSArray *)minimalCacheForFolder:(NSInteger)folderId
             article.folderId = folderId;
             article.title = title;
             article.link = link;
-            article.enclosure = enclosure;
-            article.hasEnclosure = hasenclosure_flag;
             [myCache addObject:article];
         }
         [results close];