MAINT: Move from flat-layout -> src-layout package structure

Since we now have the libedfapi folder, I think it is cleaner to keep this and eyelinkio in a src folder instead of at the root directory. This also mimics antio, and helps setuptools work automagically

Author: scott-huberty

pyproject.toml

@@ -3,8 +3,7 @@ requires = ["setuptools >= 64.0.0"]
 build-backend = "setuptools.build_meta"
 
 [tool.setuptools]
-# These are the folders that we want to include in the package
-packages = ["eyelinkio", "libedfapi"]
+package-dir = {""= "src"}
 
 [project]
 name = "eyelinkio"