Prints a type with initial colon and surrounding quotes to formatter.
DESCRIPTION
The call pp_print_type fmt ty prints the usual textual representation of the
type ty to the formatter fmt, in the form `:ty`.
To print a type with colors, use pp_print_colored_qtype.
FAILURE CONDITIONS
Should never fail unless the formatter does.
COMMENTS
The usual case where the formatter is the standard output is print_qtype.