Documentation for the GDEY075Z08 Display

[DJGummikuh]

Description:

Related issue (if applicable): Documentation for adding the GDEY075Z08 ePaper Display to the waveshare_epaper driver.

Pull request in esphome with YAML changes (if applicable): This is a hen-and-egg situation. Creating this PR first to reference it over in my esphome PR :D

Checklist:

• [x] I am merging into next because this is new documentation that has a matching pull-request in esphome as linked above.
  or

• [ ] I am merging into current because this is a fix, change and/or adjustment in the current documentation and is not for a new component or feature.

• [ ] Link added in /index.rst when creating new documents for new components or cookbook.