Add tox caching for 3.6-optional

Author: jonmmease

.circleci/config.yml

@@ -12,16 +12,16 @@ jobs:
       - checkout
       - restore_cache:
             keys:
-              - tox-v1-{{ checksum "tox.ini" }}
-              - tox-v1-
+              - py27-core-v1-{{ checksum "tox.ini" }}
+              - py27-core-v1-
       - run:
           name: Install tox
           command: 'sudo pip install tox'
       - run:
           name: Test with tox
           command: 'tox -e py27-core'
       - save_cache:
-          key: tox-v1-{{ checksum "tox.ini" }}
+          key: py27-core-v1-{{ checksum "tox.ini" }}
           paths:
             - .tox
 
@@ -142,13 +142,21 @@ jobs:
 
     steps:
       - checkout
+      - restore_cache:
+            keys:
+              - py36-optional-v1-{{ checksum "tox.ini" }}
+              - py36-optional-v1-
       - run:
           name: Install tox
           command: 'sudo pip install tox'
       - run: cd plotly/tests/test_optional/test_jupyter && npm install
       - run:
           name: Test with tox
           command: 'tox -e py36-optional'
+      - save_cache:
+          key: py36-optional-v1-{{ checksum "tox.ini" }}
+          paths:
+            - .tox
 
   "python-3.7-optional":
     docker:
@@ -224,7 +232,7 @@ workflows:
 #      - "python-2.7-optional"
 #      - "python-3.4-optional"
 #      - "python-3.5-optional"
-#      - "python-3.6-optional"
+      - "python-3.6-optional"
 #      # 3.7 optional disabled due to current shapely incompatibility
 #      # - "python-3.7-optional"
 #      - "python-2.7-plot_ly"