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

tests/test_stop_sequence.cpp

@@ -0,0 +1,22 @@
+#include "stop_waiter.hpp"
+
+#include <cassert>
+#include <iostream>
+
+int main() {
+    int stop_requests = 0;
+    int probes = 0;
+    const auto first = [&] {
+        ++stop_requests;
+        return stop_requests == 1 ? StopProbe::Unknown : StopProbe::Stopped;
+    };
+    const auto state = waitForStopped([&] {
+        ++probes;
+        return probes < 2 ? StopProbe::Unknown : StopProbe::Stopped;
+    }, std::chrono::milliseconds(10), std::chrono::milliseconds(1));
+    assert(state == StopProbe::Stopped);
+    assert(first() == StopProbe::Unknown);
+    assert(first() == StopProbe::Stopped);
+    assert(stop_requests == 2);
+    std::cout << "Stop sequence tests passed\n";
+}