Check for OSX >= 10.4 to match what the maunal says and what we actually support.

Check for OSX >= 10.4 to match what the maunal says and what we actually support.

* configure.ac: Check that OSX is 10.4 or newer.

* etc/NEWS (NextStep/OSX port changes): OSX 10.4 or newer is required.

* src/nsfns.m (Fns_list_services): Remove comment and check for OSX < 10.4.
(ns_do_applescript): Remove check for >= MAC_OS_X_VERSION_10_4.

* src/nsimage.m (setPixmapData, getPixelAtX, setAlphaAtX): Remove onTiger.

* src/nsmenu.m (fillWithWidgetValue:): Remove code for < MAC_OS_X_VERSION_10_2.

* src/nsselect.m (ns_string_from_pasteboard): Remove check for >=
MAC_OS_X_VERSION_10_4.

* src/nsterm.h (MAC_OS_X_VERSION_10_3, onTiger): Remove.
(EmacsApp): Remove check for >= MAC_OS_X_VERSION_10_4.
(struct nsfont_info): Remove check for >= MAC_OS_X_VERSION_10_3.