Following a discussion with @NelleV I suggest to decrease the number of CI builds to help easing the backlog.

• drop USE_PYTEST (now useless)

On Travis, e.g.:

• py2.7 mock numpy=1.7 pandas docs
• py3.4
• py3.6 pandas docs pep8 delete-font-cache
• osx (=2.7) mock

Note that we really should build the docs on 2.7 too (extra points if we build them on OSX instead of the Linux 2.7 job) -- right now they don't build on 2.7 at all (due to failure in examples).

On Appveyor the third job is currently a duplicate of the second(!) except that one has USE_PYTEST and not the other (which is the same). So we could be left with

• py2.7 numpy=1.8 without extra dependencies
• py3.5 numpy=1.10 without extra dependencies
• py2.7 numpy=1.10 32-bit with extra dependencies
  (the last two could be merged into e.g. py3.5 numpy=1.10 32-bit with extra dependencies, if we're still under backlog pressure)

More extra points if someone manages to build the docs on Windows...