Use travis' container-based infrastructure

.travis.yml

@@ -1,5 +1,8 @@
 language: python
 
+# use container-based infrastructure
+sudo: false
+
 python:
   - '2.6'
   - '2.7'

ci/before_install.sh

@@ -1,8 +1,9 @@
 #!/bin/bash
 set -e
 
-sudo apt-get update -qq
-sudo apt-get install -qq openjdk-7-jdk openjdk-7-jre
+# JDK is not required for JPype1 anymore
+# sudo apt-get update -qq
+# sudo apt-get install -qq openjdk-7-jdk openjdk-7-jre
 
 [ -n "$JYTHON" ] && "${TRAVIS_BUILD_DIR}/ci/before_install_jython.sh" || "${TRAVIS_BUILD_DIR}/ci/before_install_nonjython.sh"