refactor: follow best-practices in Dockerfile

Dockerfile

@@ -6,7 +6,7 @@ MAINTAINER Glenn ROLLAND <glenux@glenux.net>
 RUN apt-get update \
 	&& apt-cache search lib mysql dev$ \
 	&& apt-get install -y \
-		wget unzip curl \
+		unzip curl \
         libfreetype6-dev \
         libicu-dev \
         libjpeg62-turbo-dev \
@@ -28,9 +28,9 @@ RUN apt-get update \
 	&& docker-php-ext-install imap \
     && docker-php-ext-install zip
 
-ADD php-uploads.ini /usr/local/etc/php/conf.d/glenux-uploads.ini
-ADD php-performance.ini /usr/local/etc/php/conf.d/glenux-performance.ini
-ADD php-errors.ini /usr/local/etc/php/conf.d/glenux-errors.ini
+COPY php-uploads.ini /usr/local/etc/php/conf.d/glenux-uploads.ini
+COPY php-performance.ini /usr/local/etc/php/conf.d/glenux-performance.ini
+COPY php-errors.ini /usr/local/etc/php/conf.d/glenux-errors.ini
 
 RUN curl -sS https://getcomposer.org/installer \
   | php -- --install-dir=/usr/local/bin --filename=composer
@@ -38,8 +38,8 @@ RUN curl -sS https://getcomposer.org/installer \
 ENV DOLIBARR_VERSION=18.0.4
 # ENV DOLIBARR_VERSION=17.0.2
 # ENV DOLIBARR_VERSION=16.0.4
-RUN wget -q \
-  -O /tmp/dolibarr-${DOLIBARR_VERSION}.zip \
+RUN curl -sS \
+  -o /tmp/dolibarr-${DOLIBARR_VERSION}.zip \
   https://github.com/Dolibarr/dolibarr/archive/${DOLIBARR_VERSION}.zip
 
 RUN unzip -q -d /usr/src /tmp/dolibarr-${DOLIBARR_VERSION}.zip \
@@ -59,5 +59,5 @@ RUN sed \
   /etc/apache2/sites-enabled/000-default.conf
 
 
-CMD apache2-foreground
+CMD ["apache2-foreground"]