add ss submodules for testing

.gitmodules

@@ -1,3 +1,9 @@
 [submodule "vendor/h12.me/socks"]
 	path = vendor/h12.me/socks
 	url = https://github.com/h12w/socks
+[submodule "vendor/github.com/shadowsocks/go-shadowsocks2"]
+	path = vendor/github.com/shadowsocks/go-shadowsocks2
+	url = https://github.com/shadowsocks/go-shadowsocks2
+[submodule "vendor/github.com/Yawning/chacha20"]
+	path = vendor/github.com/Yawning/chacha20
+	url = https://github.com/Yawning/chacha20

vendor/github.com/Yawning/chacha20

@@ -0,0 +1 @@
+Subproject commit e3b1f968fc6397b51d963fee8ec8711a47bc0ce8

vendor/github.com/shadowsocks/go-shadowsocks2

@@ -0,0 +1 @@
+Subproject commit 87b55c90ac57968b4979adaef9a51c98582f76a9