Merged features for # 1.6.3 (#114)

- Added shift+click function for multi row selection to Dashboard
- Added -DBUILD_STATIC=ON/OFF option to CMake configuration to create fully static builds
- Added current algo and list of supported_varaints to login message for future usage on proxy
- Added support for latest Stellite (XTL) and Alloy (XAO) variants
- Simplification of configuration, "force-pow-variant" and "cryptonight-lite-ipbc" parameters are now deprecated see [Coin Configuration](https://github.com/Bendr0id/xmrigCC/wiki/Coin-configurations) for guidance
- Fixed leaks in transport shutdown

src/net/Connection.cpp

@@ -82,6 +82,10 @@ Connection::Ptr establishConnection(const ConnectionListener::Ptr& listener,
     }
     catch (...) {
         LOG_ERR("[%s:%d] Failed to establish connection: %s", host.c_str(), port, boost::current_exception_diagnostic_information().c_str());
+
+        if (connection) {
+            connection->disconnect();
+        }
     }