Making appname used by archiaus configurable while creating karyon zuul server.
Merge branch '2.x' of https://github.com/Netflix/zuul into 2.x
Fixing server rxnetty metrics.

The server is created before the servo module was installed.
We need to explicitly specify the metrics provider in this case.
Merge pull request #79 from NiteshKant/2.x

Making appname used by archiaus configurable while creating karyon zuul server