[t411] Increase item limit
[t411] Increase item limit

On searches for popular keywords, a feed reader not reading the feed often
enough can miss items (ie more than 5 items were added since last fetch)
so this change increases the limit from 5 items to 10 items, and retrieves
pages faster to compensate (500ms seems enough for not spamming t411).

Frenzie/rss-bridge,LogMANOriginal/rss-bridge,RSS-Bridge/rss-bridge,LogMANOriginal/rss-bridge,Riduidel/rss-bridge,sebsauvage/rss-bridge,simonbru/rss-bridge,teromene/rss-bridge,kranack/rss-bridge,mro/rss-bridge,Riduidel/rss-bridge,Frenzie/rss-bridge,griffaurel/rss-bridge,mro/rss-bridge,RSS-Bridge/rss-bridge,GregThib/rss-bridge,simonbru/rss-bridge,Riduidel/rss-bridge,kranack/rss-bridge,polo2ro/rss-bridge,ORelio/rss-bridge,kranack/rss-bridge,RSS-Bridge/rss-bridge,kranack/rss-bridge,ORelio/rss-bridge,teromene/rss-bridge,ORelio/rss-bridge