unify dockerfiles

images/php/configure_gd.sh

@@ -0,0 +1,19 @@
+#!/bin/sh
+
+PHP=$(echo "$PHP_VERSION" | cut -c -3)
+
+echo "php $PHP"
+
+if [ "$PHP" = "7.2" ] || [ "$PHP" = "7.3" ]; then
+  docker-php-ext-configure gd \
+          --with-gd \
+          --with-jpeg-dir \
+          --with-png-dir \
+          --with-zlib-dir \
+          --with-freetype-dir
+else
+  docker-php-ext-configure gd \
+          --enable-gd \
+          --with-jpeg \
+          --with-freetype
+fi