Added log file setting using named pipes unsing '.extra.heroku["log-files"]' with default log files

Just like talked about int #71.

tail log files with this synthax :
```bash
(
     tail -n0 -qF   file1.log   file2.log    file3.log
     \$pmsgr < "tail"
)&
```
Would only work if log files are touched.

Tailing on named pipes only works if I generate one command tail by file.

Not sure if it's a bug of tail ?


The nginx default setting is a fix to allow bigger header.

I used it to enable facebook and twitter OAuth protocols on some of my sites as the Navigators would send kind of big headers in those case.

I tested this on 3 different instances with more or less log files.

Doc is comming.