Add Makefiles, fix some compile errors

There are more compile errors, especially in the cross-assemblers.
But I'm leaving those for someone else.

crossassemblers/hpasm/Makefile

@@ -0,0 +1,20 @@
+# all of these can be over-ridden on the "make" command line if they don't suit your environment.
+TOOL=hpasm
+CFLAGS=-O2 -Wall -Wshadow -Wextra -pedantic -Woverflow -Wstrict-overflow
+BIN=/usr/local/bin
+INSTALL=install
+CC=gcc
+
+$(TOOL): $(TOOL).c
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) -o $(TOOL) $(TOOL).c $(LDLIBS)
+
+.PHONY: clean install uninstall
+
+clean:
+	rm -f $(TOOL)
+
+install: $(TOOL)
+	$(INSTALL) -p -m u=rx,g=rx,o=rx $(TOOL) $(BIN)
+
+uninstall:
+	rm -f $(BIN)/$(TOOL)