Conda setup for CI

[rth]

Following discussion in #180 this PR proposes a Travis CI setup using conda. Please let me know if I missed anything.

Edit: with the appveyor.yml addition this fixes #180

[nicoddemus]

@rth thanks a ton, this is great work.

I made a few comments, please take a look.

[nicoddemus]

What do you think about creating a PYQT_PACKAGE environment variable in the env section along with the others? There will be a small repetition, but I think that's OK.

[nicoddemus]

I think we can use fuzzy versions like pyside=1.*, pyqt=4.* and pyqt=5.*.

[nicoddemus]

Also please make sure to add yourself as a contributor in the README.

[coveralls]

Coverage remained the same at 100.0% when pulling 9388845 on rth:conda-CI into 12be2ab on pytest-dev:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 8c2e25a on rth:conda-CI into 12be2ab on pytest-dev:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 882d808 on rth:conda-CI into 12be2ab on pytest-dev:master.

[coveralls]

Coverage remained the same at 100.0% when pulling ea33aa2 on rth:conda-CI into 12be2ab on pytest-dev:master.

[rth]

@nicoddemus Thanks a lot for the review! I addressed your comments and added the Appveyor setup (largely inspired by the one in qtpy). Also refactored a bit travis setup to be more consistent. Tests now pass. The only point is that in Travis there is a warning/error at the very end,

Done. Your build exited with 0.
XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":99.0"
      after 2266 requests (2266 known processed) with 0 events remaining.

but I guess since tests pass that's not relevant...

[rth]

Also, there is no linting in Appveyor, but since it's already done in Travis that should, hopefully, be sufficient...

[nicoddemus]

Awesome!

I agree that we don't need to also run linting on AppVeyor, that's fine.

I commented a minor detail if you can address it, but if you are out of time we can merge as it is. 👍

[nicoddemus]

We are not using tox and coveralls here so I guess we can remove them.

[coveralls]

Coverage remained the same at 100.0% when pulling 5f2c206 on rth:conda-CI into 12be2ab on pytest-dev:master.

[rth]

Thanks, you are right - I removed tox and coveralls from the Appveyor setup..

[nicoddemus]

Awesome, thank you, really appreciate it! 👍