add unit test for lru cache

.travis.yml

@@ -9,10 +9,11 @@ cache:
 before_install:
   - sudo apt-get update -qq
   - sudo apt-get install -qq build-essential libssl-dev swig python-m2crypto python-numpy dnsutils
-  - pip install m2crypto salsa20 pep8
+  - pip install m2crypto salsa20 pep8 nose
   - sudo tests/socksify/install.sh
 script:
   - pep8 .
+  - nosetests shadowsocks/*
   - python tests/test.py -c tests/table.json
   - python tests/test.py -c tests/aes.json
   - python tests/test.py -c tests/aes-ctr.json

tests/test_latency.py

@@ -4,6 +4,7 @@ import sys
 import time
 
 
+if __name__ == '__main__':
     before = time.time()
 
     for line in sys.stdin: