remove build files from repo

public/404.html

public/LogoFZJuelich.jpg

public/LogoFZJuelich.png

public/LogoTUChemnitz.png

public/LogoUBonn.png

public/LogoUStuttgart.png

public/LogoUStuttgart.svg

public/LogoUWuppertal.png

public/LogoUWuppertal.svg

public/_footer/index.html

public/_header/index.html

public/categories/index.html

public/categories/index.xml

public/categories/page/1/index.html

public/css/auto-complete.css

public/css/bootstrap.min.css

public/css/featherlight.min.css

public/css/font-awesome.min.css

public/css/horsey.css

public/css/hybrid.css