Merge threads.h into threading/thread.h

[ShadowNinja]

Now we only have one file for thread management.

[kwolekr]

I'm not on board with changing all of the threadid_ts to something else.

[Zeno-]

This should be #ifndef USE_CPP11_THREADS, or (better) combined with the #if USE_CPP11_THREADS on line 220

[ShadowNinja]

I didn't change this line in this PR.

[nerzhul]

👎 for renaming threadid_t

[kwolekr]

Just a friendly ping on this PR.

I am on board with consolidating the threads code into a single file, but not the threadid_t rename. It seems unnecessary and setting that kind of precedent means we'd have to change content_t as well which is another big find & replace operation that doesn't actually provide tangible benefit to the project.

Could you split the two changes into distinct PRs? Or would you prefer that I close this one out for you and open a new one that just merges the threading files instead?

[nerzhul]

I have the same opinion as @kwolekr on this subject

[ShadowNinja]

@kwolekr: Changed back to global_lowercase_underscore_t style.

[nerzhul]

i'm closing this, we are near feature freeze and this part will be refactored after release to use pure C++11