Error with export-scaled

[sapper-trle]

 line 228, in python_export_scaled
    pdb.gimp_image_merge_visible_layers(copyimg, CLIP_TO_IMAGE)
NameError: global name 'copyimg' is not defined

Saved an image other than .xcf.

Also no text was being displayed in the SpinButton boxes when the dialog was shown.

I had to add second argument to SpinButton constructor to have the text shown.

percent_e = gtk.SpinButton(adj, 0)
width_e = gtk.SpinButton(adj, 0)
height_e = gtk.SpinButton(adj, 0)