Add support for 64x32 displays + higher speed I2C com

[clowrey]

New define has been setup for 64x32 displays that need an additional
starting offset value of 0x20 + the other usual changes.. Only currently
tested on 64x32 and 128x64 displays on a SAMD core board.

[mike-rankin]

Just testing the 64x32 display on my SAMD21G project and it works great! Thanks for the work.
Pic of it running is at: https://0miker0.wordpress.com/samd21g-sensor-board/

[clowrey]

I have created a video showing the library running on a 64x32 pixel OLED - I would suggest that Adafruit design and sell this OLED on a breakout board, I believe it is the smallest OLED currently produced in the world. https://www.youtube.com/watch?v=TX5S9V5ZjrQ

[tyeth]

Thank you so much for this PR 💖

It may have been almost ten years, but I've got a pair of these mini screens that previously worked in CircuitPython, and a fresh desire to get them working with WipperSnapper, so I can go ahead and hopefully integrate the work done here along with test the result.

Adafruit still don't sell one of these sized screens so that probably goes a little way to explaining the lack of response (i.e. no way to test it, along with Adafruit having a very large number of repos to maintain, so more often only the ready+testable PRs get the time invested).

The lucky thing is you published your work, so others got to use it immediately, and more may still benefit!

[tyeth]

Closed by #292 , soon to be released as version 2.5.15