0.1 update, make the stop container code more robust and fix some bugs, update the about screen for version 0.1

src/operation_state.cpp

@@ -0,0 +1,15 @@
+#include "operation_state.hpp"
+
+#include <utility>
+
+void OperationState::begin(std::string title, std::string message) {
+    busy_ = true;
+    title_ = std::move(title);
+    message_ = std::move(message);
+    result_.clear();
+}
+
+void OperationState::complete(std::string result) {
+    busy_ = false;
+    result_ = std::move(result);
+}