Use standard shared library versioning.

Do not remove static library after building.
This was also a race if MAKE_JOBS > 1.

Index: gettext-tools/gnulib-lib/Makefile.in
--- gettext-tools/gnulib-lib/Makefile.in.orig
+++ gettext-tools/gnulib-lib/Makefile.in
@@ -3542,7 +3542,7 @@ libgettextlib_la_LDFLAGS = $(AM_LDFLAGS) -no-undefined
 	$(LIB_HARD_LOCALE) $(LIB_MBRTOWC) $(LIB_POSIX_SPAWN) \
 	$(LIB_SETLOCALE) $(LIB_SETLOCALE_NULL) $(LOG10_LIBM) \
 	$(LTLIBICONV) $(LTLIBINTL) $(LTLIBUNISTRING) $(POW_LIBM) \
-	@INTL_MACOSX_LIBS@ -release @VERSION@ $(am__append_3) \
+	@INTL_MACOSX_LIBS@ $(am__append_3) \
 	$(am__append_8) $(am__append_25) $(am__append_26)
 
 # Use this preprocessor expression to decide whether #include_next works.
@@ -4553,7 +4553,7 @@ fcntl.h: fcntl.in.h $(top_builddir)/config.status $(CX
 @GL_GENERATE_GETOPT_CDEFS_H_FALSE@	rm -f $@
 
 # No need to install libgettextlib.a, except on AIX.
-install-exec-local: install-libLTLIBRARIES install-exec-clean
+install-exec-local: install-libLTLIBRARIES
 install-exec-clean:
 	case "@host_os@" in \
 	  aix*) ;; \