Set the password via the spec's rest API

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Use the real trust REST api

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
add /1.0/trust/<fingerprint> GET support

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>