Use specmap value
Use specmap on others mats
Convert remaining shaders
Some fixes
Additionnal fixes
Try to emulate enery conservation
Revert "Revert "Prepare shader for specmap value""

This reverts commit 780482edba2b0de3358f7e2139db3de3318f729e.
Merge branch 'specmap'
Fix godray opacity
Fix splatting
Tried a different layout for the checkboxes (sorry, but I didn't like the
previous approach at all). Only disadvantage now (I can think of) is that
the width of the lables is now hard coded to 40% of the screen.
Fix display of notifications.
Merge branch 'master' of github.com:supertuxkart/stk-code
Emulate envmap specular reflexion
Tweak envmap