This module is the normal way to write ocaml code that talks to the jenga server. See
rpc_intf.ml
for what kind of information can be exchanged between client and server.
The server is not specified with a host and port, but with a filesystem path to the root directory of the server (usually where the .hg/.git directory is). This implies one can only connect to jenga servers on the local machine.
module Connection_error : sig ... end