extract shared types (exceptions, enums), add module level doc, rename exception to be generic

pyHS100/__init__.py

@@ -1,5 +1,20 @@
+"""
+This module provides a way to interface with TP-Link's smart home devices,
+such as smart plugs (HS1xx), wall switches (HS2xx), and light bulbs (LB1xx).
+
+All common, shared functionalities are available through `SmartDevice` class::
+
+    x = SmartDevice("192.168.1.1")
+    print(x.sys_info)
+
+For device type specific actions `SmartBulb` or `SmartPlug` must be used instead.
+
+Module-specific errors are raised as `SmartDeviceException` and are expected
+to be handled by the user of the library.
+"""
 # flake8: noqa
 from .smartplug import SmartPlug
-from .pyHS100 import SmartPlugException, SmartDevice
+from .pyHS100 import SmartDevice
+from .types import SmartDeviceException
 from .smartbulb import SmartBulb
 from .protocol import TPLinkSmartHomeProtocol