Patch #662454: import a.b as c is ok, fixes #660811.

Doc/ref/ref6.tex

@@ -678,11 +678,7 @@ The first form of \keyword{import} statement binds the module name in
 the local namespace to the module object, and then goes on to import
 the next identifier, if any.  If the module name is followed by
 \keyword{as}, the name following \keyword{as} is used as the local
-name for the module. To avoid confusion, you cannot import modules
-with dotted names \keyword{as} a different local name. So \code{import
-module as m} is legal, but \code{import module.submod as s} is not.
-The latter should be written as \code{from module import submod as s};
-see below.
+name for the module. 
 
 The \keyword{from} form does not bind the module name: it goes through the
 list of identifiers, looks each one of them up in the module found in step