The Cayman, Tactile and Architect themes were modified from the work of
Jason Long (https://github.com/jasonlong/).

The Leonids theme was modified from the work of Renyuan Zou
(https://github.com/renyuanz/leonids).

    Copyright (c) 2015 Renyuan Zou

The HPSTR theme was modified from the work of Michael Rose
(https://github.com/mmistakes/hpstr-jekyll-theme).

    Copyright (c) 2014 Michael Rose

The pandoc template files were modified from the default template
in rmarkdown package, written by JJ Allaire.

The html_pretty() function was derived from the html_vignette() function in
rmarkdown package, written by Hadley Wickham and Yihui Xie.

The Open Sans font files included were designed by Steve Matteson.

Other part of the package was written by Yixuan Qiu.
