Add support for epd7in3e

[antoinecellerier]

• Switch back to upstream waveshareteam/e-Paper repo
• Add support for waveshare_epd.epd7in3e
  Proper color display is dependent on Fix color for 7in3e 6 color panel waveshareteam/e-Paper#363 being merged

[robweber]

Thanks for contributing. Couple of questions:

1. Have you tried the upstream waveshare repo in any long term capacity? Been a while since I've tried but there was a pretty critical error for most b/w EPDs where it would error out when trying to wake from sleep. I'll pull this and test on my own but just curious.
2. Is your 7in3e implementation dependent on the upstream merge? At first glance I'm thinking no since the method calls are the same but unsure how the changed code affects actual use.

[antoinecellerier]

I've not had the opportunity to test the upstream repo with other EPDs recently no. I only have the 7in5b and 7in3e displays so no opportunity to really test black and white :-/
The upstream merge isn't technically required for things to work, it just fixes the colors being all shuffled. e.g. blue shows up as red without the fix.