add xbasic interpreter implementation

Signed-off-by: Avinal Kumar <avinal.xlvii@gmail.com>

src/main.cc

@@ -0,0 +1,19 @@
+#include <memory>
+
+#include "xbasic/xbasic_interpreter.hpp"
+#include "xeus/xkernel.hpp"
+#include "xeus/xkernel_configuration.hpp"
+int main(int argc, char const *argv[]) {
+  // Load configuration file
+  std::string file_name = (argc == 1) ? "connection.json" : argv[2];
+  xeus::xconfiguration config = xeus::load_configuration(file_name);
+
+  // Create interpreter instance
+  using interpreter_ptr = std::unique_ptr<xbasic::xbasic_interpreter>;
+  interpreter_ptr interpreter = std::make_unique<xbasic::xbasic_interpreter>();
+
+  // Create kernel instance and start it
+  xeus::xkernel kernel(config, xeus::get_user_name(), std::move(interpreter));
+  kernel.start();
+  return 0;
+}