[scikit-image] WIP / Demo: New maxima finding algorithm(s) for 2D (#3022)

[Lars G.]

Dear devs,

I'd like to highlight this pull request
https://github.com/scikit-image/scikit-image/pull/3022
as a follow-up of an earlier discussion
https://mail.python.org/pipermail/scikit-image/2018-April/005514.html
on this mailing list.

It demonstrates two new algorithms to find local maxima inside an image.
Its performance is comparable to `feature.peak_local_max` but has the
same output as `morphology.local_maxima`.
Please have a look if you're interested.

Best regards,
Lars