Modernize C++ usage (#144)

* Stratosphere: Use modern C++ idioms in some places

* algorithms like std::for_each are used instead of raw loops

* Stratosphere: Replace more raw loops with algorithms

* Stratosphere: Add a utility predicate function to test for equality with a reference element

This can be used to rewrite some common raw loops using algorithms instead

* fs.mitm: Use variant

* fs.mitm: Use enum class

* fs.mitm: Turn RomFSSourceInfo::Cleanup into a destructor

This obsoletes the need for a custom deleter in other places

* fs.mitm: Use enum class some more

* fs.mitm: Use unique_ptr

* fs.mitm: Simplify initialization

* Stratosphere: Simplify initialization

* fs.mitm: Use unique_ptr (fix memory leak along the way)

The previous code was using "delete" rather than "delete[]"

* fs.mitm: Use vector::emplace_back rather than push_back

emplace_back constructs elements in-place, hence avoiding a redundant element copy.

* Stratosphere: Replace more raw loops with algorithms

* Stratosphere: Use unique_ptr

* fs.mitm: Replace more raw loops with algorithms

* Stratosphere: Prefer move-construction over copy-construction when moving sink parameters around

stratosphere/fs_mitm/source/fsmitm_worker.cpp

@@ -7,7 +7,7 @@ static SystemEvent *g_new_waitable_event = NULL;
 static HosMutex g_new_waitable_mutex;
 static HosSemaphore g_sema_new_waitable_finish;
 
-static WaitableManager *g_worker_waiter = NULL;
+static std::unique_ptr<WaitableManager> g_worker_waiter;
 
 Result FsMitMWorker::AddWaitableCallback(void *arg, Handle *handles, size_t num_handles, u64 timeout) {
     (void)arg;
@@ -29,11 +29,9 @@ void FsMitMWorker::Main(void *arg) {
     g_new_waitable_event = new SystemEvent(NULL, &FsMitMWorker::AddWaitableCallback);
 
     /* Make a new waitable manager. */
-    g_worker_waiter = new WaitableManager(U64_MAX);
+    g_worker_waiter = std::make_unique<WaitableManager>(U64_MAX);
     g_worker_waiter->add_waitable(g_new_waitable_event);
     
     /* Service processes. */
     g_worker_waiter->process();
-    
-    delete g_worker_waiter;
 }