Add escript option to the makefile

Signed-off-by: Jordan Wilberding <diginux@gmail.com>

Makefile

@@ -29,7 +29,7 @@ BEAMS= $(BEAMDIR)/joxa/compiler.beam $(BEAMDIR)/joxa/shell.beam \
 .SUFFIXES:
 .SUFFIXES:.jxa
 .PHONY:all bootstrap_test bootstrap_helper bootstrap setup do-changeover clean \
-	test build cucumber shell
+	test build cucumber shell escript
 
 all: build $(BEAMS)
 
@@ -54,6 +54,9 @@ cucumber: $(BEAMS)
 shell: $(BEAMS)
 	`which rlwrap` sinan shell
 
+escript: $(BEAMS)
+	sinan escript
+
 do-changeover: setup bootstrap_test bootstrap_helper $(BEAMS)
 	sinan cucumber; \
 	sinan eunit; \