hg serve: call setconfig on the parentui
It makes sense to do this on the "global" ui object, since command line
options should affect the whole process.
This should fix hg serve --style=gitweb inside a repo (part of issue253).
abort: repository a not found!
255
abort: error: Connection refused
255
abort: repository a not found!
255
abort: destination '../a' already exists
255
abort: repository a not found!
255
destination directory: q
abort: destination 'q' already exists