Reviewed by Darin Adler.

        Add "64" and "64u" make rules to allow easy building of 64-bit versions.

        make 64: will build Intel-only 64-bit.
        make 64u: will build 4-way universal for PPC and Intel.

        * Makefile:
        * Makefile.shared:

WebKitTools:

        Reviewed by Darin Adler.

        * Scripts/build-webkit: Add --universal and --64-bit flags to make building
        64-bit architectures easy. Combine the two flags to build 4-way universal.
        * Makefile: Add "64" and "64u" make rules. Fix the universal rule to return
        non-zero when the build failes.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@30597 268f45cc-cd09-0410-ab3c-d52691b4dbfc