[at-spi2-core] Remove idl directory

[Mike Gorse <mgorse src gnome org>]

commit 52968ad5f35d77d164bbce538b6ce5be5678eb39
Author: Mike Gorse <mgorse alum wpi edu>
Date:   Thu Mar 14 20:30:39 2019 -0500

    Remove idl directory
    
    These files have never been used, are not actually written in a language
    that can be automatically parsed, and have not been part of the tarball
    for some time. Removing them to avoid confusion, since having them in the
    repository makes it appear that they are used.

 idl/accessible.didl  | 234 ------------------------------------
 idl/action.didl      |  60 ----------
 idl/application.didl |  24 ----
 idl/cache.didl       |  27 -----
 idl/collection.didl  |  69 -----------
 idl/component.didl   | 181 ----------------------------
 idl/controller.didl  |  97 ---------------
 idl/device.didl      |  33 ------
 idl/document.didl    |  25 ----
 idl/event.didl       |  79 -------------
 idl/hypertext.didl   |  82 -------------
 idl/image.didl       |  42 -------
 idl/listener.didl    |   9 --
 idl/selection.didl   |  54 ---------
 idl/socket.didl      |  31 -----
 idl/table.didl       | 190 -----------------------------
 idl/text.didl        | 329 ---------------------------------------------------
 idl/types.didl       |  25 ----
 idl/value.didl       |  15 ---
 19 files changed, 1606 deletions(-)