This commit introduces support for generating snippets formatted
using Markdown. Asciidoctor remains the default.
A new SnippetFormat abstraction has been introduced with Asciidoctor
and Markdown implementations provided out of the box.
Markdown-formatted templates are also provided for all of the default
snippets.
Please refer to the updated reference documentation for further
details.
Closes gh-150
Closes gh-19
4d37dea1d6