graphics/gimp-beautify-plugin: Unbreak build after r501005

/bin/sh: /usr/local/bin//usr/local/bin/gimptool-2.0: not found
beautify.c:18:10: fatal error: libgimp/gimp.h: No such file or directory
#include <libgimp/gimp.h>

^~~~~~~~~~~~~~~~

http://beefy6.nyi.freebsd.org/data/120amd64-default/501065/logs/errors/gimp-beautify-plugin-2012.08.12.00_8.log