Merge pull request #4444 from JensNockert/pub-semaphore

Make std::sync::semaphore() public

src/libstd/sync.rs

@@ -360,7 +360,7 @@ fn access_cond<U>(blk: fn(c: &Condvar) -> U) -> U {
 struct Semaphore { priv sem: Sem<()> }
 
 /// Create a new semaphore with the specified count.
-fn semaphore(count: int) -> Semaphore {
+pub fn semaphore(count: int) -> Semaphore {
     Semaphore { sem: new_sem(count, ()) }
 }