Soyuz support

Adds a `Soyuz::Support` class that abstracts the `symbolize_keys` method into it's own module that can be used throughout the app.

Also includes this module in the `Soyuz::CommandChoice` so that the following is possible:

```yaml
defaults:
  deploy_cmd: 'echo default deploy $SOYUZ_ENVIRONMENT'

environments:
  -
    production:
      before_deploy_cmds:
        - 
          -
            display: "Run migrations"
            cmd: "echo run migrations"
          -
            display: "Skip migrations"
            cmd: "echo skipping migrations"
      after_deploy_cmds:
        - "echo after deploy callback"
  -
    staging: {}
```