Fix bug #16272 when inserting newline at point-min in electric-pair-mode. 

* elec-pair.el (electric-pair-post-self-insert-function): Don't
open extra newlines at beginning of buffer.
Fix pipe bug with OS X emacs --daemon (Bug#16262).

* emacs.c (main) [DAEMON_MUST_EXEC]: Clear the close-on-exec
flags on the daemon pipe ends before execing.
Add the "use strict;" and "use warnings;" pragmas.

* admin/make-emacs:
* admin/build-configs: Add the "use strict;" and "use warnings;" pragmas.
* configure.ac (LIBXML2_CFLAGS): Fix xcrun-related quoting problem.

Reported by YAMAMOTO Mitsuharu in:
http://lists.gnu.org/archive/html/emacs-devel/2013-12/msg00995.html
* src/emacs.c (main): [DAEMON_MUST_EXEC]: Restore close-on-exec after exec.
Revert quoting of xcrun-related library.