Volunteer can login

[maggie-larkin]

Notes

• See here for design, no need to worry about the cute graphics at the moment
• We have some of this here: https://puppy-project-test.herokuapp.com/admin/people/sign_in just not the last part where they can login
• We don't have the "Fosters Dashboard" page built that is referenced in the criteria yet but I imagine it lives at something like /fosters. I'm thinking we can redirect the user there without anything living at that page yet.
• Please give me a test email and password I can use to confirm the acceptance criteria

User Story

As a volunteer for The Little Black Dog
I want to log into the system
So that I can see the list of fosters

Acceptance Criteria

GIVEN I am on the login page
WHEN I enter an email and password that match ones in the system
THEN I am routed to the volunteer view of the "Fosters" page
AND I see "Fosters" written across the top of the page (h1)