To run tests with vscode test explorer or lua.
Adds package.searcher for __modname__ requires.
Adds some package.path(s) because path explosion will make it find the correct file.
This framework sets up the following.
Adds generic versions of global factorio functions (defines, log, table_size).
Test Explorer extension, search for tests, run tests (optionally debug tests)
Code Runner (.run) extension, just run the file
Sumneko vscode: run/debug should work.
Lua: From the mod root run lua tests/test_name.lua