Remove the shebang because the file is not executable.
Update the constructor to expect a transport config object which contains
configuration parameters such as the shared secret and Tor's data directory.
Add the function `setStateLocation()' which makes it possible to update the
constant `DATA_DIRECTORY'.
Update the default value of the constant `DATA_DIRECTORY' with what we got from
obfsproxy.
Dynamically compose the path to the client ticket file and to the server's
state file which makes it possible that `DATA_DIRECTORY' is reset during
initialisation.
The default value for the data directory should be the current directory.  That
should also work in Windows.
As the server, get the UniformDH shared secret from the constructor.
Remove `handle_server_transport_options()' since it is no longer used in
obfsproxy.  See: https://trac.torproject.org/projects/tor/ticket/8979