Move IIS server configs into a separate repository

Internet Information Services (IIS) Server Configs repository:
https://github.com/h5bp/server-configs-iis

Ref: h5bp/server-configs#161
Move lighttpd server configs into a separate repo

lighttpd Server Configs repository:
https://github.com/h5bp/server-configs-lighttpd

Ref: h5bp/server-configs#161
Move Nginx server configs into a separate repo

Nginx Server Configs repository:
https://github.com/h5bp/server-configs-nginx

Ref: h5bp/server-configs#161