travis: adapt for unittest change

.travis.yml

@@ -29,6 +29,7 @@ before_install:
 
 install:
     - sudo apt-get -y install $(./dist/tools/travis-scripts/get-pkg-list.py)
+    - sudo pip install pexpect  # current version in Ubuntu repos is errorneous
     - git config --global user.email "travis@example.com"
     - git config --global user.name "Travis CI"
     - test "$TRAVIS_BRANCH" = "master" || git fetch origin $TRAVIS_BRANCH:$TRAVIS_BRANCH

dist/tools/travis-scripts/get-pkg-list.py

@@ -37,7 +37,7 @@ common_pkgs = common_pkgs + ["cmake"]
 arm_pkgs = ["gcc-arm-none-eabi"]
 msp_pkgs = ["gcc-msp430"]
 x86_pkgs = ["qemu-system-x86", "g++-multilib", "gcc-multilib",
-            "build-essential"]
+            "build-essential","python-pip"]
 avr8_pkgs = ["gcc-avr", "binutils-avr", "avr-libc"]
 static_tests_pkgs = ["doxygen", "cppcheck"]
 all_mcu_pkgs = arm_pkgs + msp_pkgs + \