Explicitly re-export names from top-level package using __all__

This avoids the re-exports from being flagged as errors when a project
that uses Invoke is checked using `mypy --no-implicit-reexport`.

It also obsoletes all flake8 suppressions in `__init__.py`.

Author: mthuurne

invoke/__init__.py

@@ -1,10 +1,55 @@
+__all__ = (
+    "AmbiguousEnvVar",
+    "Argument",
+    "AuthFailure",
+    "Call",
+    "Collection",
+    "CollectionNotFound",
+    "CommandTimedOut",
+    "Config",
+    "Context",
+    "Executor",
+    "Exit",
+    "FailingResponder",
+    "Failure",
+    "FilesystemLoader",
+    "Local",
+    "MockContext",
+    "ParseError",
+    "ParseResult",
+    "Parser",
+    "ParserContext",
+    "PlatformError",
+    "Program",
+    "Promise",
+    "Responder",
+    "ResponseNotAccepted",
+    "Result",
+    "Runner",
+    "StreamWatcher",
+    "SubprocessPipeError",
+    "Task",
+    "ThreadException",
+    "UncastableEnvVar",
+    "UnexpectedExit",
+    "UnknownFileType",
+    "UnpicklableConfigMember",
+    "WatcherError",
+    "__version__",
+    "__version_info__",
+    "call",
+    "pty_size",
+    "task",
+)
+
+
 from typing import Any, Optional
 
-from ._version import __version_info__, __version__  # noqa
-from .collection import Collection  # noqa
-from .config import Config  # noqa
-from .context import Context, MockContext  # noqa
-from .exceptions import (  # noqa
+from ._version import __version_info__, __version__
+from .collection import Collection
+from .config import Config
+from .context import Context, MockContext
+from .exceptions import (
     AmbiguousEnvVar,
     AuthFailure,
     CollectionNotFound,
@@ -21,14 +66,14 @@
     WatcherError,
     CommandTimedOut,
 )
-from .executor import Executor  # noqa
-from .loader import FilesystemLoader  # noqa
-from .parser import Argument, Parser, ParserContext, ParseResult  # noqa
-from .program import Program  # noqa
-from .runners import Runner, Local, Failure, Result, Promise  # noqa
-from .tasks import task, call, Call, Task  # noqa
-from .terminals import pty_size  # noqa
-from .watchers import FailingResponder, Responder, StreamWatcher  # noqa
+from .executor import Executor
+from .loader import FilesystemLoader
+from .parser import Argument, Parser, ParserContext, ParseResult
+from .program import Program
+from .runners import Runner, Local, Failure, Result, Promise
+from .tasks import task, call, Call, Task
+from .terminals import pty_size
+from .watchers import FailingResponder, Responder, StreamWatcher
 
 
 def run(command: str, **kwargs: Any) -> Optional[Result]: