Various improvements (#264)

- Replace C function pointers with C++ `std::function` in `Thread`, `Timer` and `DispatcherThread`
- Rename `SystemEvent`-related functions
- WiFi: fix auto-connect when WiFi disconnects from bad signal
- WiFi: fix auto-connect when WiFi fails to auto-connect
- WiFi: implement disconnect() when tapping connected WiFi ap in WiFi management app

Tests/TactilityCore/DispatcherTest.cpp

@@ -4,26 +4,10 @@
 
 using namespace tt;
 
-static uint32_t counter = 0;
-static const uint32_t value_chacker_expected = 123;
-
-void increment_callback(TT_UNUSED std::shared_ptr<void> context) {
-    counter++;
-}
-
-void value_checker(std::shared_ptr<void> context) {
-    auto value = std::static_pointer_cast<uint32_t>(context);
-    if (*value != value_chacker_expected) {
-        tt_crash("Test error");
-    }
-}
-
 TEST_CASE("dispatcher should not call callback if consume isn't called") {
-    counter = 0;
+    int counter = 0;
     Dispatcher dispatcher;
-
-    auto context = std::make_shared<uint32_t>();
-    dispatcher.dispatch(&increment_callback, std::move(context));
+    dispatcher.dispatch([&counter]() { counter++; });
     kernel::delayTicks(10);
 
     CHECK_EQ(counter, 0);
@@ -32,24 +16,23 @@ TEST_CASE("dispatcher should not call callback if consume isn't called") {
 TEST_CASE("dispatcher should be able to dealloc when message is not consumed") {
     auto* dispatcher = new Dispatcher();
     auto context = std::make_shared<uint32_t>();
-    dispatcher->dispatch(increment_callback, std::move(context));
+    dispatcher->dispatch([]() { /* NO-OP */ });
     delete dispatcher;
 }
 
 TEST_CASE("dispatcher should call callback when consume is called") {
-    counter = 0;
+    int counter = 0;
     Dispatcher dispatcher;
 
-    auto context = std::make_shared<uint32_t>();
-    dispatcher.dispatch(increment_callback, std::move(context));
+    dispatcher.dispatch([&counter]() { counter++; });
     dispatcher.consume(100);
+
     CHECK_EQ(counter, 1);
 }
 
 TEST_CASE("message should be passed on correctly") {
     Dispatcher dispatcher;
 
-    auto context = std::make_shared<uint32_t>(value_chacker_expected);
-    dispatcher.dispatch(value_checker, std::move(context));
+    dispatcher.dispatch([]() { /* NO-OP */ });
     dispatcher.consume(100);
 }