Gems with underscore "_" in the name cannot be proxied

[eddiewebb]

Looks to be the same issue as #34 but specific to gems with "_" in the name.

I think the regexp just needs to be updated to include.

see my comment on the last fix. 15c9118#commitcomment-4191033

[tedpennings]

+1

[mkristian]

I guess I need more input since I see on the client side

$ gem install thread_safe
Fetching: thread_safe-0.1.3.gem (100%)
Successfully installed thread_safe-0.1.3
1 gem installed

and the server side has no 404 in the logs. and the regexp which caused the old problems was to store the gems into nested directories with the first letter as directory names.

so I would need more input on what exactly triggers the 404, i.e. if you use bundler the Gemfile is usually very helpful. a gist of the log might also help (debug if possible)