Move ld64 into SharedEnvExtension

Superenv is being tested on Xcode 3.1.4, so this needs to be supported
in both ENVs, not just stdenv.
Upgrading lzlib To Version 1.5

lzlib version 1.4 is no longer on this site and is 404'ing. Version 1.5 appears to be the latest release.

http://download.savannah.gnu.org/releases/lzip/

Closes #22916.

Signed-off-by: Misty De Meo <mistydemeo@gmail.com>
plzip 1.1