Enable ccache on Travis

.travis.yml

@@ -28,8 +28,9 @@ notifications:
       on_success: change
       on_failure: always
 
-cache: 
-    - apt
+cache:
+    apt: true
+    ccache: true
 
 env:
     global:
@@ -45,9 +46,12 @@ env:
       - ENABLE_MAINTAINER_ZTS=1 ENABLE_DEBUG=1
 
 before_script:
+    - ccache --version
+    - ccache --zero-stats
+    - export USE_CCACHE=1
     # Compile PHP
     - ./travis/compile.sh
-    # Setup Extensions 
+    # Setup Extensions
     - . ./travis/ext/mysql/setup.sh
     - . ./travis/ext/mysqli/setup.sh
     - . ./travis/ext/pdo_mysql/setup.sh
@@ -57,3 +61,6 @@ before_script:
 # Run PHPs run-tests.php 
 script:
     - ./sapi/cli/php run-tests.php -p `pwd`/sapi/cli/php $(if [ $ENABLE_DEBUG == 1 ]; then echo "-d opcache.enable_cli=1 -d zend_extension=`pwd`/modules/opcache.so"; fi) -g "FAIL,XFAIL,BORK,WARN,LEAK,SKIP" --offline --show-diff --set-timeout 120
+
+after_success:
+    - ccache --show-stats