Volunteer Portal - Mark yourself active when the window starts

[dherbst]

Feature Description

When a volunteer brings up the app on their phone, if they are in a volunteer window they signed up for, they should have a banner message that has a call to action to "check in" they are doing the volunteer activity.

Expected solution

Regardless of the page they are on, they see a message like:

Check in for <TaskType> now?   [ Yes ] [ Dismiss ]

Testing

[dherbst]

We don't need this for now, closing.