Support multiple functions in app.param

[tanqhnguyen]

#2603

A simple change but it might be useful in some cases where we can write shorter code to reuse middleware in app.param

[tanqhnguyen]

@dougwilson Is this one still valid?

[jonchurch]

From what I can tell, app.param is being removed from Express in v5, so unless there are still plans to land this in 4.x, this PR can likely be closed.

[dougwilson]

So app.param is not being removed in 5.0. In fact, it is being updated to include Promise support.

[jonchurch]

Ahh thank you @dougwilson, I see now that this commit was reverted by this later commit.