Fix the docs for vstack_features

2 jobs for vstack_features in 60 minutes and 7 seconds (queued for 2 seconds)
Name Stage Failure
failed
build_macosx_36 Build
   59 tests
5 failures in tests
0 failures in setup code
0 failures in cleanup code
build finished with problems.
Tests failed for bob.extension-3.1.1b0-py36hf937cbf_112.tar.bz2 - moving package to /Users/gitlab/builds/f6f95b82/0/bob/bob.extension/miniconda/conda-bld/broken
WARNING:conda_build.build:Tests failed for bob.extension-3.1.1b0-py36hf937cbf_112.tar.bz2 - moving package to /Users/gitlab/builds/f6f95b82/0/bob/bob.extension/miniconda/conda-bld/broken
TESTS FAILED: bob.extension-3.1.1b0-py36hf937cbf_112.tar.bz2
ERROR: Job failed: exit status 1
failed
build_linux_36 Build The script exceeded the maximum execution time set for the job
No URL provided, cache will not be downloaded from shared cache server. Instead a local version of cache will be extracted. 
Successfully extracted cache
$ curl --silent "${BOOTSTRAP}" --output "bootstrap.py"
$ python3 bootstrap.py -vv channel base
INFO@2019-06-06 14:06:57,116: Installing miniconda in /scratch/builds/bob/bob.extension/miniconda...
INFO@2019-06-06 14:06:57,166: Connecting to https://repo.continuum.io...
INFO@2019-06-06 14:06:57,232: (download) https://repo.continuum.io/miniconda/Miniconda3-latest-Linux-x86_64.sh -> miniconda.sh...
Pulling docker image gitlab/gitlab-runner-helper:x86_64-ac2a293c ...
ERROR: Job failed: execution took longer than 1h0m0s seconds