Prints an irts object from tseries package in Pandoc's markdown.
# S3 method for irts
pander(x, caption = attr(x, "caption"), format = panderOptions("date"), ...)
an irts object
caption (string) to be shown under the table
string passed to format when printing dates (POSIXct or POSIXt)
optional parameters passed to raw pandoc.table
function