Remove potentially unnecessary lines in Travis script.

.travis.yml

@@ -2,8 +2,6 @@ language: cpp
 compiler:
  - gcc
 before_install:
- - sudo add-apt-repository -y "deb http://archive.ubuntu.com/ubuntu/ trusty main universe"
- - sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y
  - sudo apt-get -qq update
  - sudo apt-get -qq install libgtest-dev g++-4.8 xorg-dev libglu1-mesa-dev
  - sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 90
@@ -11,6 +9,5 @@ before_install:
  - "cd glfw && mkdir build && cd build && cmake .. && make && sudo make install ; cd -"
  - "cd /usr/src/gtest && sudo cmake . && sudo cmake --build . && sudo mv libg* /usr/local/lib/ ; cd -"
 script:
- - mkdir build && cd build
- - cmake ..
+ - cmake .
  - make -j4