Revise and generalize loop parameter documentation,Remove old doc

Author: manoj-km24

Doc/library/asyncio-future.rst

@@ -53,10 +53,7 @@ Future Functions
    * a :class:`Task` object that would await on *obj*, if *obj* is an
      awaitable (:func:`inspect.isawaitable` is used for the test.)
 
-   If *obj* is neither of the above a :exc:`TypeError` is raised. The
-   optional *loop* argument takes an object of :class:`EventLoop` to
-   denote which event loop *obj* belongs to. By default *loop* is set
-   to currently running event loop.
+   If *obj* is neither of the above a :exc:`TypeError` is raised.
 
    .. important::