add ping verify (#33)

Co-authored-by: Danila Kislitsyn <dangost16@gmail.com>

Author: hleb-albau

example/example.py

@@ -79,8 +79,9 @@
     with open('document-image.jpg', 'wb') as f:
         f.write(document_image)
 
-    doc_image_quality = response.image_quality_checks()
     print("""
+    ---------------------------------------------------------------------------
+                        Web API version: {ping_version}
     ---------------------------------------------------------------------------
                    Document Overall Status: {doc_overall_status}
                     Document Number Visual: {doc_number_visual}
@@ -90,6 +91,7 @@
               MRZ-Visual values comparison: {doc_number_mrz_visual_matching}
     ---------------------------------------------------------------------------
     """.format(
+        ping_version=api.ping().version,
         doc_overall_status=doc_overall_status, doc_number_visual=doc_number_visual,
         doc_number_mrz=doc_number_mrz, doc_number_visual_validity=doc_number_mrz_validity,
         doc_number_mrz_validity=doc_number_mrz_validity, doc_number_mrz_visual_matching=doc_number_mrz_visual_matching,