Improve Dockerfile

Change order so layers can be cached more properly.

Author: erikdubbelboer

Dockerfile

@@ -1,15 +1,14 @@
 FROM composer:1.7
 
-ADD . /src/app/
-WORKDIR /src/app
-
 ENV TINI_VERSION 0.18.0-r0
 
-RUN \
-  apk add --no-cache tini=$TINI_VERSION && \
-  composer install && \
-  cp includes/config.environment.inc.php includes/config.inc.php
+RUN apk add --no-cache tini=$TINI_VERSION
+RUN composer install
 
-EXPOSE 80
+ADD . /src/app/
+
+RUN cp includes/config.environment.inc.php includes/config.inc.php
 
+WORKDIR /src/app
+EXPOSE 80
 ENTRYPOINT [ "tini", "--", "php", "-S", "0.0.0.0:80" ]