** following printf-style sequences are understood:
** .pp
** .dl
+ ** .dt %C .dd charset
+ ** .dt %c .dd reqiures charset conversion (n or c)
** .dt %D .dd deleted flag
** .dt %d .dd description
** .dt %e .dd MIME content-transfer-encoding
** .dt %n .dd attachment number
** .dt %s .dd size
** .dt %t .dd tagged flag
+ ** .dt %T .dd graphic tree characters
** .dt %u .dd unlink (=to delete) flag
** .dt %>X .dd right justify the rest of the string and pad with character "X"
** .dt %|X .dd pad to the end of the line with character "X"