Implement JWT Refresh Token

[asharron]

What was done

• Updated our JWT library to be flask_jwt_extended since it came with refresh tokens out of the box
• Updated the login route to return an access_token and a refresh_token
• Updated login logic to read from the app config for username and password
• Added a refresh api call method to the AuthService class
• Updated logic for logout button to delete tokens from storage instead of just sending you to the login screen
• Updated Login component to automatically try and use a refresh token to re-authenticate if one is present

How To Test

1. Checkout the branch on your pi
2. Within your python virutal env, run pip3 install -r requriements.txt again to download flask_jwt_extended
3. Edit line 24 of init.py for the flask server to be 5 seconds instead of 900 (so you don't have to wait 15 min to verify the refresh logic)

   JWT_ACCESS_TOKEN_EXPIRES=timedelta(seconds=900),  # 15 min

4. Start FED and BED dev servers
5. Logout on the frontend (in case you already have an access_token stored)
6. Login using the drop user name and password
7. Wait 5 seconds
8. Hit refresh
9. You should still be logged in
10. Verify the server logs show you were unauthenticated but it automatically refreshed your access_token

[nullcount]

Closes #78 #87 #86 #101

[nullcount]

I added some commits to enable changing password. Also styled the login page a bit. Added nice alerts to indicate errors, success in the login and change password process.