imagemagick6 import issue

[Sean Enck]

I was using kxstitch compiled against imagemagick V6 and it appears that 
image import doesn't work properly (running against the git head as 
we've already fixed the last issue). In V6 of imagemagick the import 
produces a completely black image. I bisected and was able to get to 
295773f44bfda1227d85edf065a8de14dc889159 as the commit that caused the 
actual regression. The gist below is a partial revert where I was able 
to successfully import an image with colors (aka not all black).

Again this only against imagemagick V6.

Patch: https://gist.github.com/enckse/de74000c2fc41c3ceb90c97fa9693250

--Sean