travis-ci: moved package management to the "apt" plugin; also removed…

… unneeded "wget".

Signed-off-by: Yichun Zhang (agentzh) <agentzh@gmail.com>

.travis.yml

@@ -9,7 +9,14 @@ compiler:
   - gcc
   - clang
 
+addons:
+  apt:
+    packages:
+    - axel
+    - cpanminus
+
 cache:
+  apt: true
   directories:
   - download-cache
 
@@ -35,9 +42,7 @@ env:
 install:
   - if [ ! -d download-cache ]; then mkdir download-cache; fi
   - if [ ! -f download-cache/openssl-$OPENSSL_VER.tar.gz ]; then wget -O download-cache/openssl-$OPENSSL_VER.tar.gz https://www.openssl.org/source/openssl-$OPENSSL_VER.tar.gz; fi
-  - sudo apt-get install -qq -y cpanminus axel
   - sudo cpanm --notest Test::Nginx Protocol::WebSocket > build.log 2>&1 || (cat build.log && exit 1)
-  - wget http://nginx.org/download/nginx-${NGINX_VERSION}.tar.gz
   - git clone https://github.com/openresty/openresty.git ../openresty
   - git clone https://github.com/openresty/nginx-devel-utils.git
   - git clone https://github.com/simpl/ngx_devel_kit.git ../ndk-nginx-module