add basic function test

update travis to run function test

function_test.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+cd `dirname $0`
+echo '-------build function test----------'
+
+FT_BUILD_DIR=ft_build
+rm -rf $FT_BUILD_DIR
+mkdir $FT_BUILD_DIR
+cd $FT_BUILD_DIR
+cmake -DBUILD_FUNCTION_TESTS=ON -DBUILD_UNIT_TESTS=OFF ..
+make cdn core ecs rds slb vpc cdn_ft core_ft ecs_ft rds_ft slb_ft vpc_ft
+
+echo '------- run function test -----------'
+
+ctest --verbose