Relaxing location data type restriction.

[dskkato]

Currently, folium.Map(location) requires location data to be an instance of list or tuple. I felt it to be inconvenient since neither numpy's array nor pandas' DataFrame cannot be used as a location argument directly. In this PR, I'm trying to relax the restriction so that any iterable object with len(location)==2 can be accepted.

[ocefpaf]

You can ignore Appveyor b/c I just merged the PR that implements it. Or rebase against latest master to get the tests going on Windows. Also, the failing notebook test seems to be a network issue. However, your change is not Python 2.7 compatible and we need a workaround there.

[dskkato]

I saw Jinja2 has similar workroud. I will try and test on Python2.7.

try:
    from collections import abc
except ImportError:
    import collections as abc

https://github.com/pallets/jinja/blob/7e417c5c6ec90709f15e96a977ab59a5397a08fb/jinja2/_compat.py#L102-L105

[ocefpaf]

I saw Jinja2 has similar workroud. I will try and test on Python2.7.

try:
    from collections import abc
except ImportError:
    import collections as abc

pallets/jinja:jinja2/_compat.py@7e417c5#L102-L105

That is probably OK until we drop support for legacy python.

[dskkato]

I would like to use Collection for validation, but it's only supported 3.6 or later. So I added one helper function for the compatibility.

[ocefpaf]

Please avoid style changes in the same PR. It makes the reviewing process a little bit harder.
(Style changes are sometimes welcomed though, but preferably in a different PR.)

[dskkato]

I reverted them. My formatter accidentally modified it...

[ocefpaf]

👍

[ocefpaf]

This is good to go IMO but I'll let it here for a few days so @Conengmo can take a second look. Planning on merging it next week.

Thanks @dskkato!

[ocefpaf]

Ooops. Wrong button! Sorry! Well... Now it is merged 😄

[Conengmo]

Looks good! Thanks for your contribution @dskkato and Filipe for the review.

[ocefpaf]

And sorry again for the premature merge! I had way too many tabs open for a Saturday morning.

[Conengmo]

No problem