[issue17374] Remove restriction against Semaphore having a negative value

[Amaury Forgeot d'Arc]

Amaury Forgeot d'Arc added the comment:

>  3. When a thread increments the semaphore, if there are other 
>     threads waiting, one of the waiting threads gets unblocked.
Is a condition missing here? "if the resulting count is positive"

Since the use case is different from a regular Semaphore, I think it make sense to have a new Barrier class.  It's not obvious for me why I need (1-n) to wait for n completed tasks.

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nosy: +amaury.forgeotdarc

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<http://bugs.python.org/issue17374>
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