Added missing logo icons and removed duplicates

Added missing logo icons for payment methods. Removed duplicate icons
from prev. version.

Prestashop 1.4 : 16x16 logo.gif
Prestashop 1.5 : 32x32 logo.png
Prestashop 1.6 : 32x32 logo.png (or font awesome)
Hook payment icon : 64x64 .png (font awesome