Update GitHub Pages compatible installation instructions
Update GitHub Pages compatible installation instructions

Replace old fork method with jekyll-remote-theme method.

marcosramon/marcosramon.github.io,mmistakes/jekyll-theme-basically-basic,mmistakes/jekyll-theme-basically-basic,marcosramon/marcosramon.github.io,mmistakes/jekyll-theme-basically-basic,marcosramon/marcosramon.github.io