Improve pid and log files settings

[jlecour]

• when processes > 1 the pid file has its increment before the extension and all pid files have their increment (not just after the first) ;
• the log file can be configured ;
• the environment is inferred.

Inspired from sidekiq/sidekiq#1539 by @seuros

[jlecour]

The second commit, about the increment is very opinionated and you're welcome to argue against it.

[jlecour]

Even with those refactorings, I still have the ghost processes issue. But I don't think it's this recipe's fault. I get a ghost process for processes >= 2 and it's created but a sidekiq bootstrap execution.

[seuros]

I think it because cap2 recipe use nohup instead of -d.

[seuros]

I pushed a new branch https://github.com/seuros/capistrano-sidekiq/tree/ghost , can you try it ?

[jlecour]

That's exactly what I figured at too. I was still having a strange behavior so I didn't send my PR yet.

[seuros]

We should change the quiet and stop tasks, it is ugly.