Merge from emacs-24 branch
Reduce use of (require 'cl).
* admin/bzrmerge.el: Use cl-lib.
* leim/quail/hangul.el: Don't require CL.
* leim/quail/ipa.el: Use cl-lib.
* vc/smerge-mode.el, vc/pcvs.el, vc/pcvs-util.el, vc/pcvs-info.el:
* vc/diff-mode.el, vc/cvs-status.el, uniquify.el, scroll-bar.el:
* register.el, progmodes/sh-script.el, net/gnutls.el, net/dbus.el:
* msb.el, mpc.el, minibuffer.el, international/ucs-normalize.el:
* international/quail.el, info-xref.el, imenu.el, image-mode.el:
* font-lock.el, filesets.el, edmacro.el, doc-view.el, bookmark.el:
* battery.el, avoid.el, abbrev.el: Use cl-lib.
* vc/pcvs-parse.el, vc/pcvs-defs.el, vc/log-view.el, vc/log-edit.el:
* vc/diff.el, simple.el, pcomplete.el, lpr.el, comint.el, loadhist.el:
* jit-lock.el, international/iso-ascii.el, info.el, frame.el, bs.el:
* emulation/crisp.el, electric.el, dired.el, cus-dep.el, composite.el:
* calculator.el, autorevert.el, apropos.el: Don't require CL.
* emacs-bytecomp.el (byte-recompile-directory, display-call-tree)
(byte-compile-unfold-bcf, byte-compile-check-variable):
* emacs-byte-opt.el (byte-compile-trueconstp)
(byte-compile-nilconstp):
* emacs-autoload.el (make-autoload): Use pcase.
* face-remap.el (text-scale-adjust): Simplify pcase patterns.
Implement cygw32

Here, we use the generic window-system configuration system we just
implemented to support the w32 window-system in the mainline build
under Cygwin.  (Previously, the w32 window system could only be
compiled as part of the NT-native Emacs build process.)

The changes in this patch need to be applied atomically in order to
avoid breaking Emacs.  The changes include:

  - Changes throughout the Lisp and C code to not assume that
      NT Emacs and the w32 window system are synonymous.

  - Wiring up the regular select(2) event loop to Windows messages

  - Cleaning up the w32 drag-and-drop receiving code.

  - Exposing Cygwin path conversion functions to elisp.

  - Unicode file dialog support when compiling for Cygwin.

  - Splitting the w32 term lisp initialization code into code
    applicable to any w32 window-system and code specific to
    system-type windows-nt.

  - Integrating the old and new w32 code into the build system.
Update copyright notices for 2013.