[RFR] Some improvements

[manuquentin]

• [x] Add empty-cmd argument
• [x] Add golang container
• [x] Add python container
• [x] Add color in gaudi output
• [x] Use declared variables in templates
• [x] Check the current version to download new templates (fixes #47)
• [x] Use first linked container if custom fastCgi is not set for an Apache container
• [x] Add a use case for each container/binary
  • [x] apache
  • [x] apache/ php
  • [x] apache / php / mysql
  • [x] bower
  • [x] couchdb
  • [x] golang
  • [x] jekyll
  • [x] varnish
  • [x] load balancing varnish
  • [x] nginx
  • [x] nginx/php
  • [x] load balancing nginx
  • [x] Master/slave mysql
  • [x] python / memcached
  • [x] nodejs
  • [x] phpmyadmin
  • [x] php
  • [x] npm
  • [x] composer
  • [x] postgresql / python
  • [x] silex / hhvm
• [x] Add a -h option
• [x] Update doc

[PopDaph]

+20,730 :open_mouth:

[manuquentin]

:two::zero::seven::eight::three: and still counting