Update resources on the resource page

Things I did:

• remove mainlines resources
  • deevad's brush pack
  • deevad's first patterns pack
• update the link to Vasco brushes
  • the old one doesn't lead to any brush pack
  • the new one lead to the old version, unfortunately
  • the other option would be to link to someone's deviantart, but that won't do because deviantart doesn't allow downloading for non-users now :( https://www.deviantart.com/grindgod/art/Krita-Modular-Brushset-v5-550590458
• reduce the width of texture pack and the video in tutorials area