add mashape sponsor
update tests to latest localtunnel client
allow subdomains up to 20 characters

- error out of subdomain outside of acceptable range
- don't check ranges in client id regex capture. If there is no client,
  just give a no client message instead of redirecting to service
  landing page

fixes #40
add max-sockets CLI argument
add test for invalid subdomain requests
fix bad matching against subdomains

Match for valid subdomains versus anything that comes before a period.

fixes #7
remove request count on homepage
log another socket error
remove old stats object properties
detect when http client request is finished and close connection

If the request is finished before we need to respond, we set a flag and
close the connection.

We also close the connection when the request finishes anyway because we
really like a new connection for each request. Things play nicer with
bouncy that way.
destroy client sockets upon error
make done a no-op if not provided
don't log bounce errors, just destroy the socket
don't log client connection errors
add nginx config as example

closes #11
update enchilada to 0.11.0
update bouncy to 3.2.2
add dotenv
add dockerfile
better handling of requests that die