Update Dockerfile with nano, yarn.

build-scripts/web/Dockerfile

@@ -38,6 +38,8 @@ RUN echo "mysql-server mysql-server/root_password_again password root" | debconf
 RUN apt-get update && \
     apt-get install --assume-yes \
     apache2 \
+    nano \
+    yarn \
     openssh-server \
     wget \
     sudo \
@@ -78,7 +80,6 @@ RUN openssl req -x509 -nodes -days 1825 -newkey rsa:2048 -keyout /tmp/apache.key
 RUN cp /tmp/apache.crt /etc/ssl/certs/server.crt
 RUN cp /tmp/apache.key /etc/ssl/private/server.key
 
-
 # Replace the default site configuration with our own.
 COPY 000-default.conf /etc/apache2/sites-available/000-default.conf
 
@@ -88,15 +89,15 @@ RUN a2enmod rewrite
 # Enable SSL
 RUN a2enmod ssl
 
-## for Content Security Policy (CSP).
+# for Content Security Policy (CSP).
 RUN a2enmod headers
 
-## Install the latest npm and gulp so we have them for responsive sites.
+# Install the latest npm and gulp so we have them for responsive sites.
 RUN sudo npm install npm@latest -g \
     sudo npm install gulp -g \
     sudo npm install bower -g
 
-## Create a symlink for node to nodejs.
+# Create a symlink for node to nodejs.
 ## RUN ln -s /usr/bin/nodejs /usr/bin/node