CI: turn on cache for osx (pandas-dev#15733)

Author: jreback

.travis.yml

@@ -28,6 +28,7 @@ matrix:
       os: osx
       compiler: clang
       osx_image: xcode6.4
+      cache: ccache
       env:
         - PYTHON_VERSION=3.5
         - JOB_NAME: "35_osx"

ci/submit_cython_cache.sh

@@ -9,7 +9,7 @@ rm -rf $PYX_CACHE_DIR
 
 home_dir=$(pwd)
 
-mkdir $PYX_CACHE_DIR
+mkdir -p $PYX_CACHE_DIR
 rsync -Rv $pyx_file_list $PYX_CACHE_DIR
 
 echo "pyx files:"