Everyone gets one person who likes to stalk and dislike your vid, no matter what. Its just part of the growth process on YT. Don't look at it as your uploading bad quality or even someone "bullying" you because in the long run 1). They're giving you a view, and 2). According to your analytics posted you have a good like/dislike ratio meaning majority of your audience likes your content. There will always be one bad apple just trying to be funny just ignore it. You're doing great ratio wise.