Added a module to support 8 character 14 segment LED displays

[pbricmont]

Tested against the Adafruit HT16K33 Breakout (PID: 1427) + 4 Dual Alphanumeric Displays (PID: 1907) using CircuitPython 3.1.2 & 4.0.0 RC1 on the Metro M0 Express, Metro M4 Express and 4.0.0 RC1 on the Metro M4 Grand Central. Also tested against a custom board based the Adafruit Alphanumeric LED Backpack. Closes issue #36.

[sommersoft]

@adafruit/circuitpythonlibrarians,

I have an open question on this:

• Would it be better to include the Seg14x8 class in the current segment.py with the other classes?
• Or, since this is not an Adafruit product (per se), is it better broken out in its own file?

I know, technically two questions...

[caternuson]

Would it be better to include the Seg14x8 class in the current segment.py with the other classes?

I think so. That would follow the existing layout.

Or, since this is not an Adafruit product (per se), is it better broken out in its own file?

Maybe. Could be in the community bundle?

[tannewt]

Community bundle is my preference. I'd really like to see chip drivers split from specific uses like the matrix defs.