Add (failing) test for #664
Possible fix for #664
flake8
Move to an elif clause of the if in line 778, as it's just another combination of mode,self.mode under the master transparency condition
remove redundant transparency check
Merge pull request #1 from wiredfool/p_rgba_transparency

Tweak for #664
Merge pull request #2 from hugovk/master

Tweak for #664
Merge pull request #665 from hugovk/transparency

Remove transparency resource after converting P->RGBA, Fixes #664