respect "working_directory" wrt config.ru
Since we added support for the "working_directory" parameter, it
often became unclear where/when certain paths would be bound.
There are some extremely nasty dependencies and ordering issues
when doing this. It's all pretty fragile, but works for now
and we even have a full integration test to keep it working.
I plan on cleaning this up 2.x.x to be less offensive to look
at (Rainbows! and Zbatery are a bit tied to this at the moment).
Thanks to Pierre Baillet for reporting this.
ref: http://mid.gmane.org/AANLkTimKb7JARr_69nfVrJLvMZH3Gvs1o_KwZFLKfuxy@mail.gmail.com