Explicitly declare decl_storage! getters as functions (#3870)

* parse decl_storage getters with fn keyword

* test for get in decl_storage

* update all decl_storage! getters

* bump version

* adjust missed doc line

substrate/srml/membership/src/lib.rs

@@ -57,7 +57,7 @@ pub trait Trait<I=DefaultInstance>: system::Trait {
 decl_storage! {
 	trait Store for Module<T: Trait<I>, I: Instance=DefaultInstance> as Membership {
 		/// The current membership, stored as an ordered Vec.
-		Members get(members): Vec<T::AccountId>;
+		Members get(fn members): Vec<T::AccountId>;
 	}
 	add_extra_genesis {
 		config(members): Vec<T::AccountId>;