This module was used when the OTP documentation was written in SGML.
It's now replaced by code in erl_docgen and therefor removed.
The option trigging the call of this module has also been removed
from the script edoc_generate.

With silent rules, the output of make is less verbose and compilation
warnings are easier to spot. Silent rules are disabled by default and
can be disabled or enabled at will by make V=0 and make V=1.

OTP-10106
OTP-10107

It is now possible to use Erlang specifications and types in EDoc
documentation. Erlang specifications and types will be used unless
there is also a function specification (@spec) or a type alias (@type)
with the same name. In the current implementation the placement of
-spec matters: it should be placed where the @spec would otherwise
have been placed.

Not all Erlang types are included in the documentation, but only those
exported by some export_type declaration or used by some documented
Erlang specification (-spec).

There is currently no support for overloaded Erlang specifications.

The syntax definitions of EDoc have been augmented to cope with most
of the Erlang types. (But we recommend that Erlang types should be
used instead.)

edoc:read_source() takes one new option, report_missing_types.
edoc_layout:module() takes one new option, pretty_printer.

          environment after a number of bugs are fixed and some features
          are added in the documentation build process.

          - The arity calculation is updated.

          - The module prefix used in the function names for bif's are
            removed in the generated links so the links will look like

            http://www.erlang.org/doc/man/erlang.html#append_element-2

            instead of

            http://www.erlang.org/doc/man/erlang.html#erlang:append_element-2

          - Enhanced the menu positioning in the html documentation when a
            new page is loaded.
          - A number of corrections in the generation of man pages (thanks
            to Sergei Golovan)
          - Moved some man pages to more apropriate sections, pages in
            section 4 moved to 5 and pages in 6 moved to 7.
          - The legal notice is taken from the xml book file so OTP's
            build process can be used for non OTP applications.