Install appropriate header files and fix the pkg-config file for the gcr

Install appropriate header files and fix the pkg-config file for the gcr

	* gcr/gcr.h:
	* gcr/gcr.pc.in:
	* gcr/gcr-certificate-basics-widget.h:
	* gcr/gcr-certificate-details-widget.h:
	* gcr/gcr-importer.h:
	* gcr/gcr-parser.h:
	* gcr/gcr-types.h:
	* gcr/Makefile.am: Install appropriate header files
	and fix the pkg-config file for the gcr library.

	* gcr/gcr-certificate.c:
	* gcr/gcr-certificate.h:
	* gcr/gcr-simple-certificate.c: (added)
	* gcr/gcr-simple-certificate.h: (added)
	* gcr/tests/ui-test-details.c:
	* gcr/tests/unit-test-certificate.c: Make GcrCertificate
	an interface so that it can more easily plug into
	various libraries.

svn path=/trunk/; revision=1481