Run examples separately from tests.

This optimizes the total run time of the Circle CI test suite.

.circleci/config.yml

 version: 2
 jobs:
-    build_py3_torch_and_tf:
+    run_tests_py3_torch_and_tf:
         working_directory: ~/transformers
         docker:
             - image: circleci/python:3.5
@@ -17,7 +17,7 @@ jobs:
             - run: sudo pip install tensorboardX scikit-learn
             - run: python -m pytest -n 8 --dist=loadfile -s -v ./transformers/tests/ --cov
             - run: codecov
-    build_py3_torch:
+    run_tests_py3_torch:
         working_directory: ~/transformers
         docker:
             - image: circleci/python:3.5
@@ -32,9 +32,8 @@ jobs:
             - run: sudo pip install pytest codecov pytest-cov pytest-xdist
             - run: sudo pip install tensorboardX scikit-learn
             - run: python -m pytest -n 8 --dist=loadfile -s -v ./transformers/tests/ --cov
-            - run: python -m pytest -n 8 --dist=loadfile -s -v ./examples/
             - run: codecov
-    build_py3_tf:
+    run_tests_py3_tf:
         working_directory: ~/transformers
         docker:
             - image: circleci/python:3.5
@@ -50,7 +49,7 @@ jobs:
             - run: sudo pip install tensorboardX scikit-learn
             - run: python -m pytest -n 8 --dist=loadfile -s -v ./transformers/tests/ --cov
             - run: codecov
-    build_py3_custom_tokenizers:
+    run_tests_py3_custom_tokenizers:
         working_directory: ~/transformers
         docker:
             - image: circleci/python:3.5
@@ -60,6 +59,21 @@ jobs:
             - run: sudo pip install pytest pytest-xdist
             - run: sudo pip install mecab-python3
             - run: RUN_CUSTOM_TOKENIZERS=1 python -m pytest -sv ./transformers/tests/tokenization_bert_japanese_test.py
+    run_examples_py3_torch:
+        working_directory: ~/transformers
+        docker:
+            - image: circleci/python:3.5
+        environment:
+            OMP_NUM_THREADS: 1
+        resource_class: xlarge
+        parallelism: 1
+        steps:
+            - checkout
+            - run: sudo pip install torch
+            - run: sudo pip install --progress-bar off .
+            - run: sudo pip install pytest pytest-xdist
+            - run: sudo pip install tensorboardX scikit-learn
+            - run: python -m pytest -n 8 --dist=loadfile -s -v ./examples/
     deploy_doc:
         working_directory: ~/transformers
         docker:
@@ -72,7 +86,7 @@ jobs:
             - run: sudo pip install --progress-bar off -r docs/requirements.txt
             - run: sudo pip install --progress-bar off -r requirements.txt
             - run: ./.circleci/deploy.sh
-    repository_consistency:
+    check_repository_consistency:
         working_directory: ~/transformers
         docker:
             - image: circleci/python:3.5
@@ -91,9 +105,10 @@ workflows:
     version: 2
     build_and_test:
         jobs:
-            - repository_consistency
-            - build_py3_custom_tokenizers
-            - build_py3_torch_and_tf
-            - build_py3_torch
-            - build_py3_tf
+            - check_repository_consistency
+            - run_examples_py3_torch
+            - run_tests_py3_custom_tokenizers
+            - run_tests_py3_torch_and_tf
+            - run_tests_py3_torch
+            - run_tests_py3_tf
             - deploy_doc: *workflow_filters