RFC 822/2068 header and unheader functions.

RFC 822/2068 header and unheader functions
 This module provides two new functions, header and unheader,
 which provide general-purpose RFC 822 header construction and parsing.
 They do not provide any intelligent defaults of HTTP-specific methods.
 They are simply aimed at providing an easy means to address the
 mechanics of header parsing.
 .
 The output style is designed to mimic CGI.pm and HTTP::Headers,
 so that users familiar with these interfaces will feel at home with
 these functions.