DESCRIPTION: Give proper version.
Literal-markdown.Rmd: Include example out.formats.

- Formatting of source Rmarkdown now supports consistent output to
  html with markdown package as well as pdf, word and html with the
  rmarkdown v2 pandoc interface.
hook_markdown.R: Typo fix startFrom check.
hook: initial latex output support.
opt_templates: give latex output 'literal-literal'

Signed-off-by: Thell Fowler <thell@tbfowler.name>