JsonFormatter not working from rake task

[svoynow]

wrong number of arguments (2 for 1)
/Users/jsmith/.rvm/gems/ruby-1.9.3-p448@myapp/gems/cane-2.6.0/lib/cane/json_formatter.rb:8:in `initialize'

It looks like when output colorization was added in 652c2f8
an options hash parameter was added to the call to initialize the formatter, but it wasn't added to the initializer for JsonFormatter.

Pull Request forthcoming