Install electron for SSB on mesh

src/freedombone-image-customise

         chroot "$rootdir" /root/npm_install.sh
     fi
 
+    chroot "$rootdir" npm install electron-prebuilt -g
+
     git clone https://github.com/ssbc/patchwork $rootdir/etc/patchwork
 
     cat <<EOF > $rootdir/usr/bin/install_patchwork