[m-rev.] for review: delete old_term_parser library from extras

[Julien Fischer]

For review by anyone.

It has been five years and three releases since the changes that
caused the addition of the old_term_parser library to the extras
were made; that is more than sufficient time for any code affected
by them to be updated.

(I've omitted the parts of the diff for the extras/old_term_parser
directory since they are just stuff being deleted.)

--------------------------------------------

Delete old_term_parser library from extras.

extras/old_term_parser/
     Delete this directory and its contents.

extras/README.md:
     Delete the entry for old_term_parser.

NEWS:
     Announce the deletion.

Julien.

diff --git a/NEWS b/NEWS
index 78e9107..c5eb774 100644
--- a/NEWS
+++ b/NEWS
@@ -241,6 +241,11 @@ Changes to the Mercury compiler
  * We have fixed a bug where `--warn-unused-imports` did not warn about
    unused modules that are also imported by an ancestor of the current module.

+Changes to the extras distribution
+----------------------------------
+
+* We have deleted the `old_term_parser` library.
+
  NEWS for Mercury 22.01
  ======================

diff --git a/extras/README.md b/extras/README.md
index 53ea6b4..f989cee 100644
--- a/extras/README.md
+++ b/extras/README.md
@@ -70,11 +70,6 @@ and many can be installed by running `mmake install`.
  * [odbc](odbc) -- A Mercury interface to ODBC (Open Database Connectivity),
    for interfacing to standard relational database packages.

-* [old_term_parser](old_term_parser) -- A library containing versions of the
-  standard library's `lexer`, `parser`, `term`, `term_io` and `varset` modules
-  as they were on 2017-02-15. Intended for backwards compatibility with older
-  code.
-
  * [posix](posix) -- A Mercury interface to some of the POSIX
    (Portable Operating System Interface) APIs.