Determines whether or not a member is able to cancel their subscription. In order to return true, the user must meet all these criteria:
- Has a recurring subscription.
- Is currently an active member (has the status "active").
- They've not already cancelled their subscription.
- Their payment profile ID has been filled out.
- $user_id - ID of the user to check. If omitted, the currently logged in user is used.
trueif the given user meets all the criteria and can cancel their subscription.
falseif they are not able to cancel their subscription.