message: fix build on OS X by convert lexical cast to variant cast,
diff: @@ -168,8 +168,9 @@ public:
  }
  const auto& idx = d.get_index<IndexType, Scope>();
  - auto lower = idx.lower_bound( boost::make_tuple(p.scope, p.code, p.table, boost::lexical_cast<typename IndexType::value_type::key_type>(p.lower_bound)) );
  - auto upper = idx.upper_bound( boost::make_tuple(p.scope, p.code, p.table, boost::lexical_cast<typename IndexType::value_type::key_type>(p.upper_bound)) );
  + auto lower = idx.lower_bound( boost::make_tuple(p.scope, p.code, p.table, fc::variant(p.lower_bound).as<typename IndexType::value_type::key_type>() ) );
  + auto upper = idx.lower_bound( boost::make_tuple(p.scope, p.code, p.table, fc::variant(p.upper_bound).as<typename IndexType::value_type::key_type>() ) );
  + // auto upper = idx.upper_bound( boost::make_tuple(p.scope, p.code, p.table, boost::lexical_cast<typename IndexType::value_type::key_type>(p.upper_bound)) );
  vector<char> data;
  