Handle a workspace directory

Hi,

Firstly, I added a way to store supervisor config dumped files, supervisor pid files and supervisor logs files in a unique workspace directory.

The config to add in config.yml is very simple :

```yml
rabbit_mq_supervisor:
    directory_workspace: %kernel.root_dir%/supervisor/%kernel.environment%
```
The tree is the following (for exemple if we follow the config above) :

```yml
app/
    supervisor/
        dev/
            dumpedConfig/
                supervisor/
                    *.conf
            logs/
            pid/
```
Secondly, I changed the program.conf.twig to handle absolute path for console, log path and prod environment (use 'in' instead of '=' in order to handle specifics environments separated with underscores or some specials caracters).

Thanks a lot for your feedback.
Best regards,
Eric Comellas