* Older versions of gnome-keyring erroneously set this content type
for passwords even though they're textual.
* If we see this content type, then check if the password is textual
and allow usage as a null-terminated password
* Schemas can also be created dynamically
* Correct introspection types for hash tables passed as args
* Validate argument hash tables
* Add some predefined schemas
* Allow allocation of pageable passwords from lookup functions
