use regular Thread objects for thread execnet model

[graingert]

No description provided.

[RonnyPfannschmidt]

do we have any backlogs on why the thread primitives where not used

this may be related to the idea of "daemon threads and when they where added to cpython

[graingert]

It's a good point: I tried the test suite with regular threads, but it hung. I needed to switch to demonic ones

[RonnyPfannschmidt]

3f9e3ca in 2013 removed using the modern primitives for the green apis

with the enhancements done in the code recently i believe it absolutely necessary to return to the rich primitives

using daemon threads is necessary - but we need to precisely pick when to use them