Unify terminology for frames in frame_to_time and get_frame.

[h-mayorquin]

Right now we have frames on the functions for getting time:
https://github.com/catalystneuro/roiextractors/blob/master/src/roiextractors/imagingextractor.py#L69

And frame_idxs in the function for getting the frames:

roiextractors/src/roiextractors/imagingextractor.py

Lines 62 to 68 in b71f17d

	def get_frames(self, frame_idxs: ArrayType, channel: Optional[int] = 0) -> np.ndarray:
	assert max(frame_idxs) <= self.get_num_frames(), "'frame_idxs' exceed number of frames"
	if np.all(np.diff(frame_idxs) == 0):
	return self.get_video(start_frame=frame_idxs[0], end_frame=frame_idxs[-1])
	relative_indices = np.array(frame_idxs) - frame_idxs[0]
	return self.get_video(start_frame=frame_idxs[0], end_frame=frame_idxs[-1] + 1)[relative_indices, ..., channel]

But both of them are referring to the same. We should use either frames, frame_idxs or frame_indices for the two of them. Numpy uses indices for their indexing routines so maybe that's a good choice:
https://numpy.org/doc/stable/reference/arrays.indexing.html#routines-indexing

But I don't think it matters that much.

[CodyCBakerPhD]

I'd vote for frames

[CodyCBakerPhD]

Although, specific to the usage in frame_to_time, how badly do we want to mimic SpikeInterface and plan to eventually just have a single get_times function that either uses an underlying irregular time_vector or otherwise returns a np.arange scaled by the sampling frequency and shifted by an offset?

https://github.com/SpikeInterface/spikeinterface/blob/master/spikeinterface/core/baserecording.py#L441-L452

[h-mayorquin]

Yeah, maybe going for get_times for consistency is better overall.