[mod] #320 #301 split check_public_key()

    check_public_key() was used for money- and wot- related commands that have differend needs.
    * remove check_public_key()
    * create is_pubkey_and_check(), check_pubkey_format() and validate_checksum()
    * create related tests
    * modify tx, balance and history commands.
    * use is_pubkey_and_check() in `id` command and solve #320

    * change imports in silkaj.money to prevent loop dependency