travis-ci: update the dependences and clean cache.

Author: logwang

.travis.yml

@@ -13,9 +13,10 @@ compiler:
 install:
   - sudo apt-get install -y coreutils build-essential git
   - sudo apt-get install -y linux-headers-`uname -r`
+  - sudo apt-get install -y libnuma-dev
 
 script:
   - make -C dpdk install T=x86_64-native-linuxapp-gcc
   - make -C lib CONF_CFLAGS="-Wno-unused-but-set-variable"
   - make -C tools
-  - make -C example
+  - make -C example