:auto should check to see which servers are available rather than default to webrick

[christiannelson]

We're using thin and it's a little inconvenient to specify -s thin in all of the places necessary. It would be groovy if :auto was a little smarter. For example, if one of thin, unicorn, etc are detected, they should be selected when using auto. If none are, then webrick is a fine last resort.

If more than one are detected, either select the first found or fallback to webrick and require one to be explicitly specified.

What do you think? If it's reasonable, I'm happy to take a stab.

[netzpirat]

This is great. We do auto detection in Guard for notification libraries by having a preferred order of libraries and pick the first that is available. I'd be glad to merge a pull request, since I'm on holiday and my coding time is limited when my family is sleeping :P

[christiannelson]

Great! I'll take a stab.

[netzpirat]

This has been released with version 1.9.0. Enjoy.