Travis: Disable OS X build since it doesn't do anything currently

.travis.yml

@@ -24,7 +24,6 @@ branches:
 
 os:
   - linux
-  - osx
 
 env:
   global:
@@ -50,10 +49,6 @@ matrix:
     - os: linux
       compiler: gcc
       env: LINUX=1 SHARED_BUILD=ON TRAVIS_NO_EXPORT=NO  ENABLE_COVERALLS=OFF
-    - os: osx
-      compiler: clang
-      osx_image: xcode8.3
-      env:
 
 install:
   - if [ $ANDROID ]; then wget -c http://dl.google.com/android/ndk/android-ndk-${PV}-${PLATF}.tar.bz2 && tar xf android-ndk-${PV}-${PLATF}.tar.bz2 ; fi