rename uvh_server_private -> uvh_server
fileserver: check stat result code
refactor refactor refactor

- add struct uvh_connection to make things simpler
    - there can be multiple requests per connection!
    - todo: pipelining support
- use SLIST from sys/queue.h to keep account of connections and requests
- refactoring here and there
move http parser settings out of struct uvh_server