fixed bug 5587, hard-coded button geometry in the property browser, fixed

	* src/nautilus-property-browser.c:
	(nautilus_property_browser_initialize), (make_category_link):
	fixed bug 5587, hard-coded button geometry in the property browser,
	fixed by removing the set_usizes and allowing gtk to adaptively
	size them and replacing the table that was holding them with a
	box so they will be centered properly.