Fix warnings in ns*m files: Replace deprecated methods, declare new interfaces.

Fix warnings in ns*m files: Replace deprecated methods, declare new interfaces.

* emacs.c: Declare unexec_init_emacs_zone.

* nsfns.m (check_ns_display_info): Cast to long and use %ld in error
to avoid warning.

* nsimage.m (allocInitFromFile): Don't use deprecated method
bestRepresentationForDevice on OSX >= 10.6.

* nsmenu.m (fillWithWidgetValue): Don't use depercated method
sizeToFit on OSX >= 10.2.

* nsselect.m (ns_string_from_pasteboard): Don't use deprecated methods
cString and lossyCString on OSX >= 10.4

* nsterm.h (MAC_OS_X_VERSION_10_3, MAC_OS_X_VERSION_10_4)
(MAC_OS_X_VERSION_10_5): Define if not defined.
(EmacsView, EmacsTooltip): Implements NSWindowDelegate on OSX >= 10.6.
(EmacsMenu): Implements NSMenuDelegate on OSX >= 10.6.
(EmacsToolbar): Implements NSToolbarDelegate on OSX >= 10.6.

* nsterm.m (keyDown): Call to wantsToDelayTextChangeNotifications and
variable firstTime not needed on OSX >= 10.6.
(setPosition): setFloatValue:knobProportion: is deprecated on OSX
>= 10.5.  Use setKnobProportion, setDoubleValue.