ARMORY-130 - Implement ArmoryD method to create a lockbox

Three salient points:

1)armoryd now loads all lockboxes used by Armory and stored in the
Armory home directory. This includes lockboxes created in armoryd.
2)Users may send lockboxes to receipients via e-mail.
3)Some lockbox creation code was broken in commit
c75d5e83e3bcffaaa08bdee442f3d0ca4f3806c7 due to a last-minute change
that wasn't properly tested. The code has been corrected.