Ensure c-f is before defaults for building docs (avoid segfault...).

.travis.yml

@@ -21,8 +21,8 @@ env:
   global:
     - PYENV_VERSION=3.6
     - PKG_TEST_PYTHON="--test-python=py36 --test-python=py27"
-    - CHANS_DEV="-c pyviz/label/dev -c ioam -c defaults"
-    - CHANS="-c ioam -c defaults"
+    - CHANS_DEV="-c pyviz/label/dev -c ioam"
+    - CHANS="-c ioam"
 
 # quick hack to determine what tag means (improvements welcome)
 #     release: ^v(\d+|\.)*[^a-z]\d*$
@@ -74,8 +74,8 @@ jobs:
       stage: docs
       env: DESC="docs"
       script:
-        # some deps only available on conda-forge
-        - doit develop_install -c conda-forge $CHANS_DEV -o doc
+        # TODO: some deps only available on conda-forge
+        - doit develop_install $CHANS_DEV -c conda-forge -o doc
         # TODO: in future PR, various doc steps will move out of .travis
         - geoviews download_data --path=examples
         - bokeh sampledata