v2.0.0-rc3

Breaking changes:

• Removed ::SendStream::consume since users should create a new SendStream instead of using this function
• Removed ::Connection::send(const std::string&,) convenience function in preparation for a better solution
• Server::Request::remote_endpoint_address and Server::Request::remote_endpoint_port
  are now functions to reduce unnecessary instructions. Also fixed issue with the
  previous variables that were not correctly set.

Notable changes:

• Added and resolved gcc and clang -Wsign-conversion warnings
• Added client support for Server Name Indication
• Implemented timeouts for SocketClient
• All boost dependencies should now be removed when using standalone asio
• Added Client::Config::header for cases where additional header fields are needed for the handshake
• Clients now accepts 101 status codes in the handshake response without checking the status code text. This resolves the issue of different servers responding with different status code texts.
• Modernized all CMakeLists.txt files, and made it easier to use
  Simple-WebSocket-Server as a sub-project
• Added MSVC support to cmake files (not tested). Some tests are disabled due to
  lacking MSVC options.
• Can now set maximum message size in WsServer:: and WsClient::config