Expose `Context` at top level

tractor/__init__.py

@@ -11,7 +11,7 @@ import trio  # type: ignore
 from trio import MultiError
 
 from .log import get_console_log, get_logger, get_loglevel
-from ._ipc import _connect_chan, Channel
+from ._ipc import _connect_chan, Channel, Context
 from ._actor import (
     Actor, _start_actor, Arbiter, get_arbiter, find_actor, wait_for_actor
 )
@@ -29,6 +29,7 @@ __all__ = [
     'open_nursery',
     'wait_for_actor',
     'Channel',
+    'Context',
     'MultiError',
     'RemoteActorError',
     'ModuleNotExposed',