build improvements, create zip file

Makefile

@@ -1,11 +1,14 @@
-SRCDIR = ./src
-all: $(SRCDIR)/*
-	mkdir -p build
+SRC_FILES := $(wildcard ./src/*.scad)
+SRC_FILES := $(filter-out ./src/blown-up-demo.scad, $(SRC_FILES))
+SRC_FILES := $(filter-out ./src/components.scad, $(SRC_FILES))
+SRC_FILES := $(filter-out ./src/roundedcube.scad, $(SRC_FILES))
+all: $(SRC_FILES)
+	mkdir -p ./build
 	for file in $^ ; do \
 		openscad -o $${file}.stl $${file} ; \
-		mv $${file}.stl build ; \
+		mv $${file}.stl ./build/ ; \
 	done
+	zip ./build/buildable-stick-system-`git describe --dirty`-stls.zip ./build/*
 
 clean:
-	rm build/*.stl
-	rmdir build
+	rm -rf ./build