Averaging mode simplification

[alecandido]

Since the current averaging mode is not consistently implemented, and pretty much confusing,

I have always found quite unintuitive how Qibolab handles the averaging modes, since as you point out the SINGLESHOT is acting differently from the others. So any attempts to make it clearer are welcome from my side.

Originally posted by @Edoardo-Pedicillo in #1120 (comment)

we may consider some better alternative to replace it.

Proposal

In principle, we may disentangle the AveragingMode just using two boolean toggles:

• average/average_shots, to decide whether to average or not
• inner_shots, to decide the placement of the shots loop

Most likely, the second parameter is not that useful on its own. But it would be anyhow used independently, both by the user and driver implementors, as it is happening in the Qblox driver.
This option is not even implemented by the QM driver

I should probably add that even the "sequential" (with average) is currently not implemented in QM, in fact it never was even for 0.1. Again, this should be possible to do, I guess I just didn't because I assumed there is no interest.

I don't fully remember why we have the AveragingMode.SEQUENTIAL in the first place. I think it was because there was a particular routine that ZI could not do with CYCLIC but I may be wrong.

Originally posted by @stavros11 in #1120 (comment)

Note

In practice, we expect a more flexible API to come with #917. In that case, the position of loops will be fully flexible, and exposed to the user. This may remove any need for more advanced and less useful options (such as inner_shots) for the sequence API.