module To_man:sig..end
Write a .man page
type man 
val new_man : unit -> man
val add_title_header : man:man -> cmd_name:string -> date:string -> short_desc:string -> unit
val add_section_header : man:man -> title:string -> unit
val add_text : man:man -> text:string -> unit
val add_newline : man:man -> unit -> unit
val add_new_para : man:man -> unit -> unit
val add_empty_line : man:man -> unit -> unit
val add_code_line : man:man -> line:string -> unit
val add_comment : man:man -> com:string -> unit
module Section_header:sig..end
val underlined_text : txt:string -> string
val bolded_text : txt:string -> string
val dash_esc : txt:string -> string
val get_result : man:man -> unit -> string