Make jpg_info return value directly useable as dict for show_image

git-svn-id: svn+ssh://rubyforge.org/var/svn/tioga/trunk/tioga@650 f6f669a6-2b79-499e-8f05-be2b991fc3d0
Remove the useless data_size dict item that prevents the results of load_png for being used directly with show_image

git-svn-id: svn+ssh://rubyforge.org/var/svn/tioga/trunk/tioga@651 f6f669a6-2b79-499e-8f05-be2b991fc3d0