Now writes PAM files when using -r, but broken for palette and transparency.  Issue 15.
Now writes PAM files when using -r, but broken for palette and
transparency.  Issue 15.


git-svn-id: 319eb561774c901116a2c19d0db24e717df3a3eb@45 40d66c6c-0ee5-11de-8837-45bce846067a

mnaberez/pypng,Scondo/purepng,drj11/pypng,Scondo/purepng,mnaberez/pypng,drj11/pypng