Replace living statue and crystal soul graphics with versions that don't have a background

- Also included is details on how this was done, in case someone else can improve on it.
- Living statue attack graphic is derived from Exile III.

rsrc/remove-bg/calc-alpha.fx

@@ -0,0 +1,49 @@
+rback=int(u[1].p{i,j}.r*255);
+gback=int(u[1].p{i,j}.g*255);
+bback=int(u[1].p{i,j}.b*255);
+
+i==21&&j==8 ? debug(rback) : 1;
+i==21&&j==8 ? debug(gback) : 1;
+i==21&&j==8 ? debug(bback) : 1;
+
+rmain=int(u[2].p{i,j}.r*255);
+gmain=int(u[2].p{i,j}.g*255);
+bmain=int(u[2].p{i,j}.b*255);
+
+i==21&&j==8 ? debug(rmain) : 1;
+i==21&&j==8 ? debug(gmain) : 1;
+i==21&&j==8 ? debug(bmain) : 1;
+
+rdiff=rmain - rback;
+gdiff=gmain - gback;
+bdiff=bmain - bback;
+
+i==21&&j==8 ? debug(rdiff) : 1;
+i==21&&j==8 ? debug(gdiff) : 1;
+i==21&&j==8 ? debug(bdiff) : 1;
+
+rgoal=rdiff > 0 ? 255 : 0;
+ggoal=gdiff > 0 ? 255 : 0;
+bgoal=bdiff > 0 ? 255 : 0;
+
+i==21&&j==8 ? debug(rgoal) : 1;
+i==21&&j==8 ? debug(ggoal) : 1;
+i==21&&j==8 ? debug(bgoal) : 1;
+
+rgd=rgoal - rback;
+ggd=ggoal - gback;
+bgd=bgoal - bback;
+
+i==21&&j==8 ? debug(rgd) : 1;
+i==21&&j==8 ? debug(ggd) : 1;
+i==21&&j==8 ? debug(bgd) : 1;
+
+ro=rgd == 0 ? 0 : rdiff / rgd;
+bo=bgd == 0 ? 0 : bdiff / bgd;
+go=ggd == 0 ? 0 : gdiff / ggd;
+
+i==21&&j==8 ? debug(ro) : 1;
+i==21&&j==8 ? debug(go) : 1;
+i==21&&j==8 ? debug(bo) : 1;
+
+max(ro,max(go,bo))