CMake 3.2 seems to be available on trusty already

.travis.yml

@@ -2,18 +2,18 @@ language: cpp
 
 os:
   - linux
-  #- osx
+  - osx
 
 dist: trusty
 sudo: required
 
 compiler:
-  #- clang
+  - clang
   - gcc
 
 env:
-  #- CONFIG=Release
-  - CONFIG=Debug
+  - CONFIG=Release
+  #- CONFIG=Debug
 
 notifications:
  email:
@@ -21,20 +21,12 @@ notifications:
    on_failure: always
 
 install:
+  - g++ --version
+  - cmake --version
   - git clone https://github.com/HowardHinnant/date
   - cd date
   - git checkout tags/v1.0.0
   - cd ..
-  - g++ --version
-  - cmake --version
-  - if [ "$TRAVIS_OS_NAME" == "linux" ]; then
-    sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
-      && sudo add-apt-repository -y ppa:george-edison55/cmake-3.x
-      && sudo apt-get update
-      && sudo apt-cache madison cmake
-      && sudo apt-get install cmake -y
-      ;
-    fi
 
 before_script:
    - mkdir build