Support multiple clients simultaneously

Fixed #34

tests/test_multi_client_it.py

@@ -0,0 +1,26 @@
+import unittest
+
+from tests.test_client_it import ClientTestCase
+from webdav3.client import Client
+
+
+class MultiClientTestCase(ClientTestCase):
+    options2 = {
+        'webdav_hostname': 'https://wrong.url.ru',
+        'webdav_login': 'webdavclient.test2',
+        'webdav_password': 'Qwerty123!',
+        'webdav_override_methods': {
+            'check': 'FAKE',
+            'download': 'FAKE',
+            'upload': 'FAKE',
+            'clean': 'FAKE',
+        }
+    }
+
+    def setUp(self):
+        super(ClientTestCase, self).setUp()
+        self.second_client = Client(self.options2)
+
+
+if __name__ == '__main__':
+    unittest.main()