Sort files from hosts

Resume files by host. I hope you enjoy with this challenge

Input

dartacan: /etc/hosts
dartacan: /etc/httpd/conf/httpd.conf
dartacan: /opt/scripts/list_vhosts
mozart: /etc/resolv.conf
mozart: /usr/bin/vim
mozart: /usr/bin/awesome
mozart: ~/.gem/ruby/2.1.0/bin/vimgolf
gullit: /bin/bash
gullit: /etc/hosts
gullit: /usr/bin/xorg
gullit: /usr/bin/xeyes
gullit: /usr/bin/X
gullit: /

Output

dartacan: /etc/hosts /etc/httpd/conf/httpd.conf /opt/scripts/list_vhosts
mozart: /etc/resolv.conf /usr/bin/vim /usr/bin/awesome ~/.gem/ruby/2.1.0/bin/vimgolf
gullit: /bin/bash /etc/hosts /usr/bin/xorg /usr/bin/xeyes /usr/bin/X /