Require a newer version of CMake.

.travis.yml

@@ -2,10 +2,11 @@ language: c
 
 before_install:
   - sudo add-apt-repository -y ppa:ubuntu-sdk-team/ppa
+  - sudo add-apt-repository -y ppa:kalakris/cmake
   - sudo apt-get update -q
 
-    # install libtoxav dependencies
-  - sudo apt-get install -y libopus-dev libvpx-dev
+    # install libtoxav dependencies and a newer version of cmake
+  - sudo apt-get install -y libopus-dev libvpx-dev cmake
 
 install:
   - _libsodium_version=1.0.0

CMakeLists.txt

@@ -17,7 +17,7 @@
 # along with Tox-WeeChat.  If not, see <http://www.gnu.org/licenses/>.
 #
 
-cmake_minimum_required(VERSION 2.8.7)
+cmake_minimum_required(VERSION 2.8.11)
 
 project(tox-weechat C)