relocatable-prog: Use wrapper-free installation on Mac OS X, take 2. This approach supports relocatable installation of shared libraries which depend on other shared libraries from the same package. * m4/relocatable.m4 (gl_RELOCATABLE_BODY): Determine use_macos_tools. If use_macos_tools is true, use reloc-ldflags and set LIBTOOL to be a wrapper around the original LIBTOOL. * build-aux/reloc-ldflags: Add support for Mac OS X, which uses the token '@loader_path' instead of '$ORIGIN'. * build-aux/libtool-reloc: New file. * modules/relocatable-prog (Files): Add it. * doc/relocatable-maint.texi (Supporting Relocation): Update to match the recent changes. Document the need to set the *_LDFLAGS of libraries. RELOCATABLE_LIBRARY_PATH and RELOCATABLE_CONFIG_H_DIR should be set in Makefile.am, not in configure.ac.

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