Skip Image.py and Image_df.py tests for Ubuntu 14 (#149)

Author: Stephen0620

src/python/tests_extended/test_docs_example.py

@@ -70,6 +70,14 @@ def test_examples(self):
                     'NaiveBayesClassifier_df.py'
                     ]:
                     continue
+            # skip for ubuntu 14 tests
+            if platform.linux_distribution()[0] == 'Ubuntu' and platform.linux_distribution()[1][:2] == '14':
+                if name in [
+                    # libdl needs to be setup
+                    'Image.py',
+                    'Image_df.py'
+                    ]:
+                    continue
             # skip for centos7 tests 
             if platform.linux_distribution()[0] == 'CentOS Linux':
                 if name in [