Help adding E-Ink display support

I'd actually create a new tab in the IDE for your eink file, and choose to save to storage as a file called 'eink'.

Then you can upload, and go to the other tab and then upload that one to test.

Or... if I'm just wanting to iterate quickly, sometimes I just put exports={}; at the head of the file, put the module contents in, and the code that uses it at the bottom (using export.fn() instead of require("eink").fn), and upload that to flash.

At least then you can just change+upload+test very quickly.