remove route mocking MADNESS from tests

OHHHHHHHHHHHHHH
DEEEEEEEEAAAAAAAAAAAAAAARRR
GAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAWWWWWWWWWD

My fellow commiters...
PRAIIIIIIIIIIIISE THE LOOOOORD AND AAAAAAAALEEELUHIAAAAAAAAAAAAAAAAH

The mocks are GOOOOOOOOOOOOOOOOOOOOOOOOOOOONE
VANISHED !
DISAPPEARED !
DELETED !
RID OF FOR GOOD !
WILL NO LONGER WALK ON THE FACE OF THE EARTH !
THY EVIL HAS BEEN PURGED FROM OUR SOIL FOR ETERNITY !

No longer will I cringe in pain or be plagued by fear every time I run
the tests. I can now rest in peace knowing that mock's mockery will
can longer mock me. HA ! WHO'S THE BOSS NOW ? HUH ?! Ain't so tough now
eh, mocky guy ? I'll be the one doing the mocking now !
MOUAHAHAHAHAHAHAHAHAHAHAH !

Seriously though, Never... EVER... TRY TO MOCK DECORATORS... AGAIN.
Before even considering mocking a decorator, always remember that the
guy (me) who ends up maintaining your code will be a violent psycopath
who knows where you live.

Some people, when confronted with a decorator they want to test, think
"I know, i'll use a mock." Now they have two problems.

Without further ado, I now declare this code smell fixed.
Happy future testing !
delete old http digest authentication

will be replaced by flask-httpauth
create wrapper around flask-httpauth

We still want requests made from localhost to bypass
authentication. So, we wrap the login_required decorator
to check where the request comes from
replace xivo_realm_digest with flask-httpauth
convert exception_catcher into error response generator
use make_error_response as flask error handler

using flask's error handling mecanism causes less bugs
in unit tests than using a decorator to catch all exceptions
add missing tests for restapi_auth
add flask-httpauth as a dependency
mock get_password before authentication is established

since get_password is referenced in RestApiAuth.__init__(),
function patches don't mock the DAO early enough
avoid calling the DAO when running on localhost

Also needed to avoid mocking the DAO for all resource tests
add missing requirement
fix flask app name in tests
fix typo/wrong comment