akt create: create the keystore

Usage: akt create <keystore.akt> [--counter-range min:max]
              [--split COUNT] [--force] [--gpg USER1 ... USERN]

  The create command is used to create the new keystore file.
  By default the PBKDF2 iteration counter is in range 500000..1000000.
  You can change this range by using the `--counter-range` option.
  High values provide best password protection at the expense of speed.

  The `--split` option indicates to separate the data blocks
  from the encryption keys.  The option defines the number of data
  storage files which are created and used by default.

  When the `--gpg` option is used, the keystore is protected by
  using gpg and one of the user's GPG key.
