[WIP]Support multiple environments

fix #4 multiple environments
fix #5 test of phantomjs
fix #6 path of '/home/git' or '/vagrant'


For development.

1. vi Vagrantfile
2. s/production/development/
3. vagrant up
4. vagrant ssh
5. cd /vagrant/gitlab
6. bundle exec foreman start

For test

Same with step 5.
6. bundle exec rake spinach
7. bundle exec rake rspec