Change ml_ms4alg to mountainsort4

[khl02007]

The algorithm for mountainsort4 was in ml_ms4alg but has recently been cleaned up and is now in mountainsort4 (https://github.com/magland/mountainsort4, also available on PyPI). This PR changes the reference to ml_ms4alg in spikesorters to mountainsort4.

@magland I assume this is OK?

[khl02007]

The build failed with the error AttributeError: module 'dask' has no attribute 'delayed' but I don't get this error when I run pytest locally. Perhaps this is related to the way dask is installed on the CI server? @alejoe91

[alejoe91]

Thanks for the change @khl02007

Let's ping @magland on this. Maybe we need to pin to a specific dask version?

[alejoe91]

@magland @khl02007 even after installing dask[complete] mountainsort seems to hang forever on travis. Jeremy any idea what's going wrong here?

[khl02007]

@alejoe91 I noticed that the cleaned up mountainsort4 package no longer has code for computing the noise overlap quality metric (the mountainsort4_curation function), presumably because all quality metrics are now computed by spiketoolkit. I don't know if this is causing the problem but I will fix this and resubmit

[samuelgarcia]

@khl02007 : you patch this, could also do it in the futur release directly in https://github.com/SpikeInterface/spikeinterface ?

[alejoe91]

@samuelgarcia I think that the patch might be directly to the mountainsort4 package