Dataset3d support show()

[bobleesj]

What this PR does

Visualize time-series, tomography, etc.

API design:

# Dataset3d.show() API
data.show()                          # all frames in 4-column grid
data.show(index=0)                   # single frame
data.show(index=-1)                  # last frame
data.show(ncols=2)                   # 2 columns
data.show(title="DP")                # titles: "DP 0", "DP 1", ...
data.show(suptitle="Time series")    # figure super title
data.show(cmap="viridis")            # colormap
data.show(cbar=True)                 # colorbar
data.show(scalebar=False)            # disable scalebar
fig, axes = data.show(returnfig=True)  # get figure for customization

Notebooks:
dataset3d_visualization.ipynb

What should PR reviewer(s) do

Please feel free to test the notebook and evaluate its API design

[bobleesj]

@ceobrero Could you pls review this and stress test this? since you have thousands of times-series data, that would quite help!