message: Read default eosio key from config.ini in addition to command line
diff: #include <boost/filesystem/path.hpp>
  #include <chrono>
  +#include <fc/io/json.hpp>
  +
  namespace fc { class variant; }
  namespace eosio {
  @@ -23,7 +25,7 @@ wallet_manager& wallet_plugin::get_wallet_manager() {
  }
  void wallet_plugin::set_program_options(options_description& cli, options_description& cfg) {
  - cli.add_options()
  + cfg.add_options()
  ("wallet-dir", bpo::value<boost::filesystem::path>()->default_value("."),
  "The path of the wallet files (absolute path or relative to application data dir)")
  ("unlock-timeout", bpo::value<int64_t>(),
  @@ -51,7 +53,8 @@ void wallet_plugin::plugin_initialize(const variables_map& options) {
  wallet_manager_ptr->set_timeout(t);
  }
  if (options.count("eosio-key")) {
  - auto eosio_wif_key = options.at("eosio-key").as<std::string>();
  + std::string eosio_wif_key = options.at("eosio-key").as<std::string>();
  + eosio_wif_key = fc::json::from_string(eosio_wif_key).as<std::string>();
  wallet_manager_ptr->set_eosio_key(eosio_wif_key);
  }
  }
  