Make sure everything is compiled prior to starting tests

Makefile

@@ -17,7 +17,7 @@ create_testdbs:
 	psql -h 127.0.0.1 -p 10432 template1 < ./test_data/test_schema.sql
 	psql -h 127.0.0.1 -p 10432 epgsql_test_db1 -c "INSERT INTO schema_version (version) VALUES ('${LASTVERSION}');"
 
-test:
+test: compile
 	@$(REBAR) eunit
 
 performance_test: compile