Update README to support relative asset links

As of January 20th, GitHub supports relative links to assets within a
repository. See [this blog
post](https://github.com/blog/1395-relative-links-in-markup-files) for
more information.
Add Molokai theme

Colorscheme based off the
[molokai](https://github.com/tomasr/molokai) for vim.

Differences from the Monokai Soda theme:

- The third color (33, 34), which is traditionally yellow is a pastel
  yellow compared with orange (33) and yellow (43)
- The fourth color (34, 44), which is traditionally blue is a pastel
  blue compared with a lavender purple
- The fifth color (35, 45), which is traditionally magenta is a pastel
  purple compared with a (repeated) pink color
- The background color is slightly darker
Add xrdb file for and update Molokai theme

Also fix mistake where the version of the Molokai theme committed to the
repo was an intermediary file used for creating the xrdb file (this file
contained all the Molokai theme RGB values on a 0 - 255 scale). The
current file is now correct.
Merge pull request #15 from Z1MM32M4N/master

Add new theme: Molokai