Support typed path parameters in route paths

[Harshal96]

Motivation:

Closes #2860

This PR adds the syntax proposed in the issue:

router.get("/users/:id:int").handler(ctx -> {
  int id = Integer.parseInt(ctx.pathParam("id")); // guaranteed to be an integer
});

[vietj]

@Harshal96 we need a test that uses an invalid type, e.g. /id:foo

[Harshal96]

@vietj have accommodated the feedback

[Harshal96]

@vietj good for another review?

[vietj]

after looking at this again, the syntax to declare a type is ambiguous with a second parameter.

we can follow the same syntax as SQL query with :: instead of :.

so example should be

router.route("/blah/:id::integer").handler(rc -> rc.response().setStatusMessage(rc.pathParam("id")).end());

[Harshal96]

@vietj updated : -> ::