DOC: some cleaning up for subplots demo in Gallery?

Proposal 1:

Background

Currently, there are a few very similar demos/examples for subplots in Gallery:

Multiple subplots:

• examples/subplots_axes_and_figures/subplot.py
• Create 2 subplots using pyplot style
• And this example is also appears and explained in the introductory Pyplot tutorial.

Basic Subplot Demo:

• examples/subplots_axes_and_figures/subplot_demo.py
• Almost the same with Multiple subplots example, but using OOP style.

Figure Title:

• examples/subplots_axes_and_figures/figure_title.py
• Basic Subplot Demo plus titles setting (OOP style).

Clean up proposal

How about merge these three as one demo using OOP style such as: Subplots With Title, and in this demo, add a link to the Pyplot tutorial so as to refer to pyplot style.

Proposal 2:

Background

And also in the Gallery, there is Creating multiple subplots using plt.subplots:

• examples/subplots_axes_and_figures/subplots_demo.py
• Although the file name is really similar to the Basic Subplot Demo (subplots_demo.py vs subplot_demo.py), this one actually serves as a gentle introduction of plt.subplots usage.

Clean up proposal

How about move this article from Gallery to the Introductory level of Tutorial as Subplots Tutorial. Since there are GridSpec guide and Tight Layout guide existed in Intermediate level of Tutorial, I think this can also smooth the transition.

And, if these proposals are acceptable, I am willing to do the work :)