Refactor probegroup to be array-based

[alejoe91]

In #416 we extended the ProbeGroup with a get_slice method. However, the current probe-centric implementation makes it difficult to slice in device channel indices from different probes are interleaved.

This PR refactors the ProbeGroup to be based on a _self.contact_array:

• when a new probe is added, its array presentation is added to the _self.contact_array and we store probe contours and annotations (contact_annotations are in the array)
• the probes is not a property that reconstructs the probes on-the-fly
• importantly, changing annotations and contact annotations for a probe in a probegroup is now disabled. Added an annotate_probe(probe_index, **kwargs) to annotate probes in the probe group

Related to SpikeInterface/spikeinterface#4465, since we want to store a probegroup object directly, but we need to sort it/silce it according to the device_channel_indices

[samuelgarcia]

@alejoe91 we should make a very clear doc here for the new behavior.
We could explain teh why (need of global conact order across probes)
And also metioning the previous behavior (list of probe) and what cannot be possible now (annotate after)

[samuelgarcia]

There is still an issue with this PR we need to solve : the to_dict/from_dict() and json will NOT preserve the contact order... We need to find something for it!!!

Give me a chance to add more complex test for orderings the probe group and global channel indices.

I propose a switch of version to 0.4.

[h-mayorquin]

I am taking a look. I will publish a review later today