Make device initialisation easier by reducing required imports (#936)

Adds username and password arguments to discovery to remove the need to import Credentials.
Creates TypeAliases in Device for connection configuration classes and DeviceType.
Using the API with these changes will only require importing either Discover or Device
depending on whether using Discover.discover() or Device.connect() to 
initialize and interact with the API.

kasa/tests/test_device_factory.py

@@ -17,10 +17,10 @@ from kasa.device_factory import (
     get_protocol,
 )
 from kasa.deviceconfig import (
-    ConnectionType,
     DeviceConfig,
-    DeviceFamilyType,
-    EncryptType,
+    DeviceConnectionParameters,
+    DeviceEncryptionType,
+    DeviceFamily,
 )
 from kasa.discover import DiscoveryResult
 from kasa.smart.smartdevice import SmartDevice
@@ -31,12 +31,12 @@ def _get_connection_type_device_class(discovery_info):
         device_class = Discover._get_device_class(discovery_info)
         dr = DiscoveryResult(**discovery_info["result"])
 
-        connection_type = ConnectionType.from_values(
+        connection_type = DeviceConnectionParameters.from_values(
             dr.device_type, dr.mgt_encrypt_schm.encrypt_type
         )
     else:
-        connection_type = ConnectionType.from_values(
-            DeviceFamilyType.IotSmartPlugSwitch.value, EncryptType.Xor.value
+        connection_type = DeviceConnectionParameters.from_values(
+            DeviceFamily.IotSmartPlugSwitch.value, DeviceEncryptionType.Xor.value
         )
         device_class = Discover._get_device_class(discovery_info)
 
@@ -137,7 +137,7 @@ async def test_connect_http_client(discovery_data, mocker):
         host=host, credentials=Credentials("foor", "bar"), connection_type=ctype
     )
     dev = await connect(config=config)
-    if ctype.encryption_type != EncryptType.Xor:
+    if ctype.encryption_type != DeviceEncryptionType.Xor:
         assert dev.protocol._transport._http_client.client != http_client
     await dev.disconnect()
 
@@ -148,7 +148,7 @@ async def test_connect_http_client(discovery_data, mocker):
         http_client=http_client,
     )
     dev = await connect(config=config)
-    if ctype.encryption_type != EncryptType.Xor:
+    if ctype.encryption_type != DeviceEncryptionType.Xor:
         assert dev.protocol._transport._http_client.client == http_client
     await dev.disconnect()
     await http_client.close()