add PAIA auth method to reset passwords

Add support of notifications (#64)

Add patron field 'note'

Make header Access-Control-Allow-Headers mandatory (#56)

Extend login with OAuth client credentials grant

Introduce conditions and confirmations

PAIA auth requires application/x-www-form-urlencoded (#50)

remove request field doc.storage, deprecate doc.storageid

support content-negotiation for languages (issue #32)

add patron types