fix "parallel computing" doc: remove extraneous "forwards"

"Julia from `v0.5` forwards natively supports multi-threading"
became
"Julia forwards natively supports multi-threading", where
the "forwards" doesn't make much sense anymore.

Author: rfourquet

doc/src/manual/parallel-computing.md

@@ -218,7 +218,7 @@ too.
 
 # [Multi-Threading (Experimental)](@id man-multithreading)
 
-In addition to tasks Julia forwards natively supports multi-threading.
+In addition to tasks Julia natively supports multi-threading.
 Note that this section is experimental and the interfaces may change in the future.
 
 ## Setup