TST: Add pandas wheels to Travis build

[gfyoung]

• Add pandas 0.20.1 and master to Travis.
• Drop 0.16.2 and Python 3.4 machines.

Closes #307.

[jreback]

needs a rebase

also why don't we xfail the failing tests for the moment, just to get a green build (and create an issue to revert this).

[gfyoung]

@jreback : Sure thing. I think what I'll do is put together a PR to patch the tests that will also close #303.

[gfyoung]

@jreback : Also see my question about the availability of 0.20.1 on conda channels in the original issue here. So we might be able to get all green for everything but the 0.20.1 and master machines for now.

[gfyoung]

@jreback : Rebase is done, but I want to fix up the master build because there is no reason to be installing numpy from source.

[jreback]

conda install pandas -c conda-forge will get you the latest (defaults is usually a few days behind on a new release)

[jreback]

pip install numpy pytz python-dateutil here, remove the conda install pandas and this should work.

[gfyoung]

I would go with conda install numpy pytz python-dateutil, but yes, point well taken.

[gfyoung]

@jreback : No longer an issue it seems. Also, FYI, when I install from the daily builds, it also pulls in the daily numpy build too (so not necessary to install numpy first, but still useful to install dependencies).

[jreback]

@jreback : No longer an issue it seems. Also, FYI, when I install from the daily builds, it also pulls in the daily numpy build too (so not necessary to install numpy first, but still useful to install dependencies).

see my comment.when using pip, you need to satisfy its deps first.

[gfyoung]

@jreback : Not necessarily, as pip takes care of that for you. But will change nonetheless.

[gfyoung]

@jreback : I fixed the installation for the master machine. Ready to merge now.

[jreback]

prob should say only supports >= 0.17.0 or something. can you add a whatsnew/0.4.0 (and add this).

[gfyoung]

@jreback : Sounds good will do (also drop Python 3.4).