DOC: adopt the SciPy Code of Conduct

[grlee77]

As discussed in #267, this PR adopts the Code of Conduct from SciPy.

I did not make any changes to the terms aside from renaming the project and committee members and removing mention of NumFOCUS as we are not a NumFOCUS-sponsored project. My changes to the CoC text are isolated to commit 8da2b32.

I think the main drawback here as compared to SciPy itself is the smaller committee size and the lack of a good alternative reporting mechanism without NumFOCUS support. That may be the best we can do for now, but let me know if you have any other ideas.

I suppose one alternative would be to also solicit an additional committee member from the broader scientific Python community.

[rgommers]

we may want to invite a third person here, perhaps from scikit-image since they rely on pywavelets and likely someone on that team will be happy to help out?

[grlee77]

Should we also include the committee member's email addresses here? (or were those deliberately omitted to reduce spam?)

[rgommers]

It shouldn't be needed I think. And if someone really wants to find us, they can look at the commit log so it's not impossible. I'd leave it out here.

[rgommers]

LGTM. Let's leave it open for some days, this is an important topic so let's make sure to give anyone interested in it the time to respond.

@PyWavelets/core-contributors any comments or approvals?

[grlee77]

@alexdesiqueira (a scikit-image core dev) has kindly volunteered to serve as a participant on our committee. I will update the text to reflect this soon.

[rgommers]

Thanks for offering to help @alexdesiqueira!

[rgommers]

No more commments in the last week, so let's get this in. Thanks a lot for doing this @grlee77, and @alexdesiqueira for volunteering to be on the committee.