Restore GDB/MI fuctionality removed by r99212

[Eli Zaretskii]

This change:

    revno: 99756
    committer: Nick Roberts <address@hidden>
    branch nick: trunk
    timestamp: Sun 2010-03-28 02:27:43 +1300
    message:
      Restore GDB/MI fuctionality removed by r99212:

      added:
        lisp/progmodes/gdb-mi.el
      removed:
        lisp/progmodes/gdb-ui.el
      modified:
        doc/emacs/building.texi
        doc/emacs/emacs.texi
        etc/NEWS
        lisp/Makefile.in
        lisp/progmodes/gud.el

has no entries in the pertinent ChangeLog files.  I think it should
have them.

Also, I think ldefs-boot.el should be updated as well, as it now has
references to gdb-ui.el that is no longer in the tree.