Update patch level for php & publish docker image latest with git hash (#45)

* publish docker image latest with git hash
* update patch levels for php
diff --git a/core/php7.1Action/Dockerfile b/core/php7.1Action/Dockerfile
index d451144..c9ef0fa 100644
--- a/core/php7.1Action/Dockerfile
+++ b/core/php7.1Action/Dockerfile
@@ -15,7 +15,7 @@
 # limitations under the License.
 #
 
-FROM php:7.1.18-alpine
+FROM php:7.1.23-alpine
 
 RUN \
     apk update && apk upgrade && \
diff --git a/core/php7.2Action/Dockerfile b/core/php7.2Action/Dockerfile
index fb08b24..fcfd481 100644
--- a/core/php7.2Action/Dockerfile
+++ b/core/php7.2Action/Dockerfile
@@ -15,7 +15,7 @@
 # limitations under the License.
 #
 
-FROM php:7.2.6-alpine
+FROM php:7.2.12-alpine
 
 RUN \
     apk update && apk upgrade && \
diff --git a/tools/travis/publish.sh b/tools/travis/publish.sh
index dfd5ab3..42e37ef 100755
--- a/tools/travis/publish.sh
+++ b/tools/travis/publish.sh
@@ -40,4 +40,15 @@
 -PdockerRegistry=docker.io \
 -PdockerImagePrefix=${IMAGE_PREFIX} \
 -PdockerImageTag=${IMAGE_TAG}
+
+  # if doing latest also push a tag with the hash commit
+  if [ ${IMAGE_TAG} == "latest" ]; then
+  SHORT_COMMIT=`git rev-parse --short HEAD`
+  TERM=dumb ./gradlew \
+  :core:php${RUNTIME_VERSION}Action:distDocker \
+  -PdockerRegistry=docker.io \
+  -PdockerImagePrefix=${IMAGE_PREFIX} \
+  -PdockerImageTag=${SHORT_COMMIT}
+  fi
+
 fi