Install the latest `knife-solo` gem library to support `environment`.
Introduce `development` environment.
[sensu-custom] Support `environment`
[fluentd-custom] Support `environment`
[growthforecast] Support `environment`
[jenkins] Support `environment`
[kazu634] Support `environment`
[webapp] Support `environment`
[wordpress] Support `environment`
Modify recipes in order to follow the `foodcritic`'s advice.
Merge pull request #132 from kazu634/environment_support

Support knife `environment` configuration.