Import pkg-config-0.19, updated version of devel/pkgconfig.

Import pkg-config-0.19, updated version of devel/pkgconfig.
News:

2005-07-16  Tollef Fog Heen

	* configure.in: Release 0.19

2005-07-15  Tollef Fog Heen

	* pkg.c (package_get_var): Make sure to g_strdup all the return
	values and not return some values which should not be freed and
	some which should.  Yay valgrind.  Freedesktop #3682

	* configure.in: Fix default search path to be pkgconfig rather
	than pkg-config again.  Freedesktop #3662

	* pkg.m4: Add a missing AC_MSG_RESULT.  Thanks to Gary Kramlich
	for noticing this and harassing me to fix it.

2005-06-29  Tollef Fog Heen

	* configure.in: Release 0.18.1

	* pkg.m4: Brown bag fix.  pkg_failed was always set to “untried”.
	Debian #316181.

2005-06-27  Tollef Fog Heen

	* configure.in: Rename to pkg-config.

pkg-config 0.18

 The inter-library dependencies check was too tight and caused
 problems if one used the --no-undefined flag to libtool on Solaris
 (since it there expands to -Wl,-z,defs which disallows undefined
 symbols).  Add a new name to .pc files: Libs.private which will
 not be listed in the output of --libs unless --static is also
 given.

 Private libraries are libraries which are needed in the case of
 static linking or on platforms not supporting inter-library
 dependencies.  They are not supposed to be used for libraries
 which are exposed through the library in question.  An example of
 an exposed library is GTK+ exposing Glib.  A common example of a
 private library is libm.

 Generally, if include another library's headers in your own, it's
 a public dependency and not a private one.

 Thanks a lot to James Henstridge for both the bug and the following
 discussion.