Warzone 2100 Graphic Mods tools

Merge safety0ff code with shield effects, added shield.c and shield.h to contain all of the major code for shield hits.

Remove second pass from Mesh::importFromOBJ that was added to gloss over
a bug, and fix the code the way it should have been fixed.

Ensure that scale isn't used uninitialised, also correct a typo.

Use the computed pie values for the shield scale.

adding pie file that was missed on my net outage commit
hitsphere.pie

adding pie hit file and textures for hit effect

perfecting forcefields and adding pie3 ssphere.pie

texture change to forcefield

Turn off shields for scav units. (Requires testing)

Update scale.