[build] Rename gPXE to iPXE

Access to the gpxe.org and etherboot.org domains and associated
resources has been revoked by the registrant of the domain.  Work
around this problem by renaming project from gPXE to iPXE, and
updating URLs to match.

Also update README, LOG and COPYRIGHTS to remove obsolete information.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/core/open.c

@@ -21,10 +21,10 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <stdarg.h>
 #include <string.h>
 #include <errno.h>
-#include <gpxe/xfer.h>
-#include <gpxe/uri.h>
-#include <gpxe/socket.h>
-#include <gpxe/open.h>
+#include <ipxe/xfer.h>
+#include <ipxe/uri.h>
+#include <ipxe/socket.h>
+#include <ipxe/open.h>
 
 /** @file
  *
@@ -73,7 +73,7 @@ int xfer_open_uri ( struct xfer_interface *xfer, struct uri *uri ) {
  * Open URI string
  *
  * @v xfer		Data transfer interface
- * @v uri_string	URI string (e.g. "http://etherboot.org/kernel")
+ * @v uri_string	URI string (e.g. "http://ipxe.org/kernel")
  * @ret rc		Return status code
  *
  * The URI will be regarded as being relative to the current working