Compiles a Markdown file to HTML.
# S3 method for default
compileMarkdown(filename, path=NULL, ..., outPath=".", header=NULL,
  metadata=getMetadata(filename), verbose=FALSE)Returns the pathname of the generated HTML document.
The filename and (optional) path of the Markdown document to be compiled.
Additional arguments passed to markdownToHTML.
The output and working directory.
character vector of valid HTML strings that should be added to the HTML <head> section.
A named list with meta data that will add as <meta> tags in the HTML <head> section.
See Verbose.
Henrik Bengtsson
The input encoding is based on getOption("encoding") and
  the output encoding is "UTF-8"
  (forced by markdownToHTML).
Internally, markdownToHTML is used.