added php7.0-mbstring

Author: Evgeny Marchenkov

Dockerfile

@@ -7,7 +7,7 @@ RUN apt-get --yes --force-yes update \
     && echo "deb http://packages.dotdeb.org jessie all" > /etc/apt/sources.list.d/dotdeb.list \
     && curl -sS https://www.dotdeb.org/dotdeb.gpg | apt-key add - \
     && apt-get update -qq -y \
-    && apt-get --yes --force-yes install php7.0-cli php7.0-apcu php7.0-apcu-bc php7.0-curl php7.0-json php7.0-mcrypt php7.0-opcache php7.0-readline php7.0-mysql php7.0-xml php7.0-zip \
+    && apt-get --yes --force-yes install php7.0-cli php7.0-apcu php7.0-apcu-bc php7.0-curl php7.0-json php7.0-mcrypt php7.0-opcache php7.0-readline php7.0-mysql php7.0-xml php7.0-zip php7.0-mbstring \
     && curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
 # Install Node.js