solidify now stores the context of sessions in project description files.

- solidify/Makefile (OBJS): added project.o
- solidify/Makefile (new): new target to create a new project
- solidify/Makefile (run): changed to resume previously created project
- solidify/util.h (stralloc): added stralloc (from fped)
- solidify/project.h, solidify/project.c: create, load, and save project
  description files
- solidify/solidify.c (clicked, gui_buttons, gui, main): updated to use
  project instead of solid
- solidify/solidify.c (usage, main): new invocation: four arguments to start
  new project, one argument to resume old project

solidify/Makefile

@@ -12,8 +12,8 @@
 
 SHELL = /bin/bash
 
-OBJS = array.o face.o histo.o level.o matrix.o overlap.o solid.o solidify.o \
-       style.o util.o
+OBJS = array.o face.o histo.o level.o matrix.o overlap.o project.o solid.o \
+       solidify.o style.o util.o
 
 CFLAGS_WARN = -Wall -Wshadow -Wmissing-prototypes \
 	      -Wmissing-declarations -Wno-format-zero-length
@@ -59,10 +59,14 @@ FACE_A=$(DIR)/ben-batcvr-outside-100um.txt.bz2
 FACE_B=$(DIR)/ben-batcvr-inside-100um.txt.bz2
 D=1.16
 
-.PHONY:		run pov disp
+.PHONY:		new run pov disp
+
+new:		solidify
+		rm -f batcvr.sfy
+		./solidify batcvr.sfy $(FACE_A) $(FACE_B) $(D) >batcvr.inc
 
 run:		solidify
-		./solidify $(FACE_A) $(FACE_B) $(D) >batcvr.inc
+		./solidify batcvr.sfy >batcvr.inc
 
 pov:
 		povray +A -W1280 -H1024 main.pov