Emerald offline wallet command line interface.

Usage:
  emerald server [options] [--port <port>] [--host <host>]
  emerald -V | --version
  emerald -h | --help

Options:
  -h, --help                                  Show this message
  -V, --version                               Show current version
  -q, --quiet                                 Only errors printed to the output
  -v, --verbose                               Verbose output
      --host <host>                           Listen host [default: 127.0.0.1]
      --port <port>                           Listen port [default: 1920]
      --base-path <path>                      Base directory path, if omitted default os-specific value will be used:
                                                  + Mac OS X: ~/Library/Emerald
                                                  + Linux: ~/.emerald
                                                  + Windows: %USERDIR%\.emerald
      --security-level <normal|high|ultra>    Level of security for cryptographic operations [default: normal]
  -c, --chain <mainnet|testnet>               Chain name [default: mainnet]