Bug 21082: Update OverDrive authentication method

Bug 21082: Update OverDrive authentication method

Testing will require an OverDrive account, you should be able to obtain a
developer account here:
https://developer.overdrive.com/

You will need to register a SIP connection for patron authentication

To test authentication:
 1 - Set authname default in OD prefs
 2 - Sign in as a patron whose branch matches authname
 3 - Verify the patron can sign into OverDrive
 4 - Set the patrons branch authname to be incorrect
 5 - Verify branch specific authname is used and patron cannot sign in
 6 - Set the default authname to be incorrect and patron's branch
 authname to be correct
 7 - Verofy patron can sign in

To test circulation:
 1 - Fill out all OD prefs and enable circulation
 2 - Sign in to opac
 3 - Verify you have an OverDrive tab
 4 - Click 'Login to Overdrive'
 5 - If password required you shoudl be prompted, otherwise you should be
signed in and see account info
 6 - Test logging out and in
 7 - Log-in, perform a search on the opac - you should see hold/checkout
buttons
 8 - Test the buttons
 9 - After holding/checking out items, check your account page
10 - Verify info is correct
11 - Log out of overdrive
12 - Search catalog click overdrive results
13 - Test "Login to Overdrive" link on OD results
14 - Verify page is reloaded, buttons show and work

Signed-off-by: Sandy Allgood <sandy.allgood@citruslibraries.org>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>