Add command bcdb to bootstrap the configuration

[C0rWin]

Currently, when setting up the configuration of BCDB server it assumed that replica's crypto material and admin's are generated off the band. What could be done instead is to add a new command to the bcdb to force generation of the material and first configuration by bcdb instance itself.

Namely one will be able to do:

bcdb init

to generate required materials and then

bcdb start

to initialize the instance.