added error info for better explanation

Fixed/Added error info when you run `$ jruby -S cap deploy production`:

    cap aborted!
    undefined method `instance' for Capistrano::Configuration:Class
    /home/surya/.rvm/gems/jruby-1.7.6/gems/torquebox-capistrano-support-3.0.1/lib/torquebox/capistrano/recipes.rb:215:in `(root)'
    org/jruby/RubyKernel.java:1082:in `require'
    /home/surya/.rvm/gems/jruby-1.7.6/gems/torquebox-capistrano-support-3.0.1/lib/torquebox-capistrano-support.rb:1:in `(root)'
    org/jruby/RubyKernel.java:1082:in `require'
    /home/surya/.rvm/gems/jruby-1.7.6/gems/torquebox-capistrano-support-3.0.1/lib/torquebox-capistrano-support.rb:18:in `(root)'
    org/jruby/RubyKernel.java:1101:in `load'
    /home/surya/Desktop/surya/work/codes/projects/job/resolutions/Capfile:1:in `(root)'
    /home/surya/Desktop/surya/work/codes/projects/job/resolutions/Capfile:27:in `(root)'
    /home/surya/.rvm/gems/jruby-1.7.6/gems/capistrano-3.0.1/lib/capistrano/application.rb:22:in `load_rakefile'
    org/jruby/RubyKernel.java:1101:in `load'
    /home/surya/.rvm/gems/jruby-1.7.6/bin/cap:23:in `(root)'