Setting up Github Markdown previews in BBEdit

1. Install redcarpet gem, as used by Github (see details here)

   $ gem install redcarpet

2. Change directory to the BBEdit application support location, and create the Packages directory if it isn't already there:

   $ cd ~/Library/Application\ Support/BBEdit/
   $ [ ! -d Packages ] && mkdir Packages

3. Enter the package directory and clone the github repo to an appropriately named directory:

   $ cd Packages
   $ git clone https://github.com/gavinaiken/bbedit-scripts.git markdown-github.bbpackage

4. Optionally, if you want to make the Github Flavored Markdown preview style the default for all markdown files, you can add symlinks to the css and filter files using the included script, i.e.:

   $ cd ~/Library/Application\ Support/BBEdit/Packages/markdown-github.bbpackage
   $ ./create-symlinks.sh

5. Now use Markup > Preview in BBEdit on any markdown.