Adapt ND to changes in code where 0 means no limit (#3258)

+ reorganize config, improved comments

plugins/newsdownloader.koplugin/feed_config.lua

@@ -1,8 +1,11 @@
 return {
 	-- list your feeds here:
-	-- only supports http URL for now
-    { "http://www.pcworld.com/index.rss", limit = 1 },
+
     { "http://feeds.reuters.com/Reuters/worldNews?format=xml", limit = 2},
-	-- set limit to "0" means no download, "-1" no limit.
-    { "http://www.football.co.uk/international/rss.xml", limit = 0 },
+    -- set 'limit' to change number of 'news' to be downloaded from source
+    -- 'limit' equal "0" means no limit.
+    { "http://www.pcworld.com/index.rss", limit = 1 },
+
+    -- comment out line to stop downloading source
+    --{ "http://www.football.co.uk/international/rss.xml", limit = 0 },
 }