Install curl inside the docker image

.travis.yml

@@ -1,10 +1,5 @@
 sudo: required
 
-addons:
-  apt:
-    packages:
-    - curl
-
 services:
   - docker
 

docker/Dockerfile.centos5-linux-x86_64-pic

@@ -1,7 +1,7 @@
 FROM centos:5
 MAINTAINER Taro L. Saito <leo@xerial.org>
 
-RUN yum -y install make gcc gcc-c++ glibc-devel perl wget bzip2 \
+RUN yum -y install make gcc gcc-c++ glibc-devel perl wget bzip2 curl \
  && rm -rf /var/lib/apt/lists/*
 
 RUN mkdir /tmp/work \