Itertools needs new maintainers

[sheganinans]

There are plenty that are willing to help:

@bluss I'd be interested in helping maintain itertools if you're still looking for someone. I'm a member of the rustsim organization, a regular contributor to nalgebra, and a drive-by contributor of API improvements to many libraries.

Originally posted by @jswrenn in #348 (comment)

[jswrenn]

Happy update: I'll be taking ownership of maintaining itertools! My first priority is going to be tackling the backlog of open PRs. :)

[Avi-D-coder]

@jswrenn If you ever want help, or more eyes for code reviews. I would be happy to help out.

[sheganinans]

Thanks! Glad to hear this is moving in the right direction. This should be a pretty significant improvement for the community!